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REESE  LIBRARY 

OF  THK 

UNIVERSITY  OF  CALIFORNIA 


Accession  No.   /8  ?00    .   Class  No. 


THE  INTERNATIONAL  SCIENTIFIC  SERIES. 
VOLUME   LIII. 


THE 

INTERNATIONAL  SCIENTIFIC  SERIES. 


EACH   BOOK   COMPLETE   IN   ONE  VOLUME,  12MO,  AND   BOUND   IN   CLOTH. 


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New  York:  D.  APPLETON  &  CO.,  1,  3,  &  5  Bond  Street 


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New  York:  D.  APPLETON  &  CO.,  1,  3,  &  5  Bond  Street. 


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late  WILLIAM  KINGDON  CLIFFORD.     $1.50. 

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University  of  Berlin.     With  63  Illustrations. 


New  York:  D.  APPLETON  &  CO.,  1,  3,  &  5  Bond  Street. 


THE  INTERNATIONAL  SCIENTIFIC  SERIES 


THE  MAMMALIA 


IN  THEIR 


RELATION  TO  PRIMEVAL  TIMES. 


BY 

OSCAR  SCHMIDT 

PROFESSOR  IN   THJUWH¥BRSl£Y  OP  BTRASBTTRO 


WITH  FIFTY-ONE   WOODCUTS 


NEW  YORK 
D.    APPLETON    AND    COMPANY 

1,  3,  AND  5  BOND  STREET 

1886 


B1OLOG/ 

LIBRARY 

G 


PREFACE. 


IN  the  Preface  to  the  Third  Edition  of  my 
'  Doctrine  of  Descent  and  Darwinism,'  which  ap- 
peared in  1883,  I  quoted  the  opinion  of  a  famous 
lawyer  as  to  the  worthlessness  of  science,  not 
with  the  intention  of  refuting  it,  but  gave  it  as 
an  example  of  the  incredible  naivete  with  which 
eminent  representatives  of  certain  pronounced 
religious  tendencies  confront  the  work  and  results 
of  natural  science.  Not  long  afterwards  I  was 
asked  by  a  well-known  man  whether  my  lectures 
on  zoology,  at  the  university,  treated  of  Darwinism 
as  well.  What  my  answer  was  is  known  to  all 
those  who  have  taken  any  interest  in  the  '  theory 
of  descent.'  To  those  who  have  an  understanding 
of  the  subject,  and  of  the  aims  of  a  scientific 
interpretation  of  the  living  world  (which  is,  in 


vi  PREFACE 

fact,  the  only  one  possible  interpretation),  I  offer 
the  present  work  as  a  supplement.  It  will  be 
found  to  contain  proofs  of  the  necessity,  the  truth, 
and  the  value  of  Darwinism  as  the  foundation 
for  the  theory  of  descent,  within  a  limited  field, 
and  is  brought  down  to  the  most  recent  times. 
Within  these  limits  the  work  is  complete  in  itself; 
for  although  the  student  of  natural  history  may 
have  become  acquainted  with  interesting  fragments 
of  the  actual  science,  still  the  subject  has  not 
before  been  presented  in  so  comprehensive  a 
manner,  or  in  so  convenient  a  form. 

Together  with  my  special  studies  of  the  zoology 
of  the  lower  animals,  I  have  for  many  years  past 
felt  myself  peculiarly  attracted  by  the  advance  of 
our  knowledge  of  the  Mammalia  in  their  general 
relation  to  paleontology  and  anthropology. 
From  year  to  year  I  have  followed  this  advance 
with  increased  interest,  and  always  with  a  view 
to  the  principal  questions  connected  with  the 
domain  as  a  whole.  Hence  I  venture  to  offer  this 
work  to  our  younger  and  rising  scientists  as,  I 
trust,  a  suggestive  introduction  to  that  portion 


PREFACE  Vii 

of  the  animal  kingdom  which   stands   closest   to 
anthropology. 

My  materials  have  been  drawn  from  original 
works,  when  and  wherever  they  were  within  my 
reach ;  hence  I  never  give  extracts  from  extracts. 
I  take  it  for  granted  that  my  readers,  if  not  already 
in  some  measure  acquainted  with  the  forms  and 
mode  of  life  of  the  Mammalia,  have  at  hand  some 
such  work  as  Brehm's  *  Thierlehen,'  or  Martin's 
'  Illustrirte*  Naturgeschichte  der  Thiere.'  Books 
such  as  these,  which  nowadays  occupy  a  pro- 
minent place  in  popular  literature,  make  us 
acquainted  with  facts;  but,  with  the  exception 
of  C.  Vogt's  and  Specht's  works  on  the  Mammalia, 
they  go  no  farther.  Now,  as  the  theory  of  descent 
has  shown,  light  and  interpretation  are  shed  upon 
the  Present  by  the  Past ;  and  thus  the  history  of 
the  development  of  animals,  the  history  of  the 
earth  and  geography,  are  made  to  confirm  one 
another.  In  undertaking  to  give  an  introduction 
to  illustrate  this,  I  must  observe  that  it  will  be 
possible  only  by  overcoming  a  variety  of  difficul- 
ties, by  entering  upon  various  apparently  trifling 


Vlll  PREFACE 

details — for  instance,  the  construction  of  the  teeth ; 
and  these  must  not  be  regarded  in  themselves  as 
merely  amusing  or  entertaining,  for,  when  brought 
into  connection,  these  details  often  open  up  the 
most  surprising  and  most  wonderful  prospects. 
By  these  enquiries  we  do  not  indeed  arrive  at  the 
final  cause  of  things,  or  at  what  the  philosophers 
call  the  Thing  Itself,  but  from  an  insight  into  the 
connection  of  the  facts  we  obtain  a  higher 
arrangement  for  those  facts.  They  demand  an 
ever  deeper  penetration,  and  transport  us  into  that 
creative  state  of  enthusiasm  which,  by  being  the 
imaginative  faculty  of  thinking-man,  raises  us 
above  those  who  remain  standing  amid  their  own 
surroundings  either  in  a  state  of  blank  amazement 
or  of  dull  enjoyment. 

I  am  only  following  the  usual  custom  by  men- 
tioning, in  conclusion,  the  assistance  I  have  re- 
ceived from  my  daughter  Johanna,  to  whose 
experienced  hand  I  owe  a  series  of  original  draw- 
ings, from  which  my  illustrations  have  beem  made. 

OSCAR  SCHMIDT. 
STRASBURG  :  September,  1884. 


CONTENTS. 


PAGR 

PEEFACE v 


I.     GENERAL  INTRODUCTION. 

1.  THE  POSITION  OF  MAMMALS  IN  THE  ANIMAL  KINGDOM.    .  1 

2.  PHENOMENA  OP  CONVERGENCE 14 

3.  THE  DISTINCTIVE  CHARACTERISTICS  OF  MAMMALS  .        .    .  30 

4.  THE   EXTENSION    OF    PAL^EONTOLOGICAL     SCIENCE    SINCE 

CUVIER 45 

5.  THE  STRATA  OF  THE  TERTIARY  FORMATION  .        .        .    .  77 

II.  SPECIAL   COMPARISON  OF  THE  LIVING 
MAMMALS  AND   THEIR  ANCESTORS. 

1.  THE  MONOTREMA,  CLOACAL  OR  FORKED  ANIMALS       .        .  86 

2.  THE  MARSUPIALS ,        ,    .  93 

3.  THE  EDENTATA,  OR  ANIMALS  POOR  IN  TEETH    .         .        .  110 

4.  THE  UNGULATA,  OR  HOOFED  ANIMALS 126 

PAIR-HOOFED   ANIMALS. 

1.  The  Suidse,  or  Pigs 137 

2.  The  Hippopotamus,  or  Kiver  Horse  .         .        .    .  144 

3.  The  Ruminants 150 

4.  Camels 154 

6.  Deer  and  their  Kindred  Forms     ....  153 

6.  Hollow-horned  Animals,  Antelopes  and  Oxen  .  173 

2 


CONTENTS 


ODD-HOOFED   ANIMALS. 

PA  OR 

1.  Tapirs  and  Khinoceros 190 

2.  The  EquidsB,  or  Horses    .        .        .        .        .    .  201 

6.  THE  ELEPHANTS 227 

6.  THE  SIBENIA,  OB  SEA-Cows 242 

7.  THE  CETACEA,  OB  WHALES 246 

8.  THE  CABKIVOBA,  OB  FLESH-EATERS 259 

9.  THE  SEALS 287 

10.  THE   INSECTIVOBA,    OB    INSECT-EATERS.    THE    KODENTS. 

THE  BATS 291 

11.  THE  PBOSIMI^E,  OB  SEMI-APES.     SIMISS,  OB  APES.     THE 

MAN  OF  THE  FUTUBB 294 


INDEX.  303 


1LLUSTEATIONS. 


FIO.  FA  fTB 

1.  Right  hand  of  a  River  Tortoise 36 

2.  A.  Lower  jaw  of  Plagiaulax  minor        ....  99 
B.  Lower  jaw  of  Plagiaulax  medius .         .        ...  99 

3.  A.  Lower  jaw  of  Neoplagiaulax 101 

B.  Lower  jaw  of  Bettongia  penicillata      .        .        .    .  101 

4.  Skull  of  Diprotodon  australis        .....  103 

5.  Skull  of  the  Wombat  (Phascolarctus  fuscus)  .        .      .  105 

6.  Skull  of  Nototherium,  side  view 105 

7.  Skull  of  Nototherium,  front  view 106 

8.  Skull  of  the  Giant  Sloth 113 

9.  Skull  of  the  Three-toed  Sloth 115 

10.  Head  of  Glyptodon  clavipes 124 

11.  Left  fore-foot  of  Anoplotherium        .         .        .         .    .  129 

12.  Left  fore-foot  of  the  Peccary 130 

13.  Coryphodon.     Right  fore  and  hind  foot    .        .        .    .  132 

14.  Coryphodon.     Skull  with  brain 134 

15.  A  Tuberculate  and  a  Crescentic  Tooth      .        .        .    .  138 

16.  Right  fore-foot  of  a  Pig 140 

17.  Palffiochrerus  typus,  left  upper  jaw 143 

18.  Second  lower  molar  of  the  Hippopotamus,  to  the  right  145 

19.  First  upper  molar  of  the  Hippopotamus,  to  the  right  .  146 

20.  Hippopotamus,  right  fore-foot 147 

21.  I.  Right  upper  cheek-tooth  of  a  Calf,  before  cutting  the 

gum 153 

II.  Right  cheek-tooth  of  a  Calf,  after  cutting  the  gum, 

artificially  polished,  from  behind  and  the  outside  153 

22.  Auchenia  hesterna.     Second  left  upper  cheek-tooth     .  157 


Xll  ILLUSTRATIONS 

FIG.  PAttB 

23.  Prox  furcatus.     Left  antler 1GO 

24.  A.  Left  fore-foot  of  the  Bed  Deer 162 

B.  Left  fore-foot  of  the  Roe 162 

C.  Second  row  of  tarsals  and  metatarsals  of  Gelocus  .  162 

25.  A.  Left  fore-foot  of  Hysemosehus  aquaticus      .        .    .  168 
J5.  Left  fore-foot  of  Hyopotamus 168 

26.  Skull  of  a  Short-horned  Bull 175 

27.  Skull  of  the  Gazelle 176 

28.  Skull  of  the  Bison  americanus          .        .        .        .    .  180 

29.  Skull  of  the  Anoa 181 

30.  Skull  of  Cainotherium  metopias 183 

31.  Skull  of  the  Tapir  (Tapirus  americanus)      .        .        .191 

32.  Back  molar,  below  to  the  left,  of  Lophiodon  parisi- 

ensis 192 

33.  Skull  of  Elasmotherium 197 

34.  A.  Skull  of  Brontotherium  ingens 199 

B.  The  same  from  above  with  a  drawing  of  the  brain .  199 

35.  Palseotherium.     Hipparion.     Horse          .        .         .    .  202 

36.  Left  hind-foot  of  Anchitherium 204 

37.  Right  upper  cheek-tooth  of  the  Horse       .        .        .    .  209 

38.  Foot  of  the  fossil  Horses  of  North  America  .         .         .  213 

39.  Macrauchenia  patagonia .  229 

40.  Polished  molar  of  Mastodon  angustidens      .        .         .  232 

41.  Portion  of  a  cheek-tooth  of  Mastodon  elephantoides    .  233 

42.  Portion  of  a  cheek-tooth  of  the  Mammoth,  polished 

sideways 235 

43.  Skull  of  Dinotherium  giganteum       .         •         .         .    .  237 

44.  Skull  of  Dinoceras  mirabile 241 

45.  Skull  of  the  Delphinus  lagenorhynchus,  Gray  .         .    .  249 

46.  Right  fore-leg  of  Delphinus  delphis      ....  250 

47.  Tooth  of  Squalodon 253 

48.  Teeth  of  the  Fox 261 

49.  Lower  jaw  of  Icticyon 266 

50.  Skull  of  Tillotherium  fodiens,  from  above     .        .        .  286 

51.  Foetal  teeth  of  the  Greenland  Seal 290 


THE    MAMMALIA 

IN  THEIE  BELATION  TO  PEIMEVAL  TIMES. 


I. 

GENERAL  INTRODUCTION. 

THE    POSITION    OF    THE    MAMMALIA   IN    THE    ANIMAL 
KINGDOM. 

IT  has  always  been  considered  a  matter  of  course 
that  the  Mammalia  stand  at  the  head  of  the  animal 
kingdom.  This  has  been  the  opinion  of  the  multi- 
tude who  have  not  given  any  thought  whatever  to 
the  origin  of  living  things ;  also  of  those  to  whom 
the  '  idea  of  the  creation,'  or  rather  the  empty  word 
creation,  was,  and  still  is,  the  one  *  comforter  in 
need ; '  and  again  also  of  the  majority  of  our  stu- 
dents of  modern  biology,  the  advocates  of  the  theory 
of  descent,  and  their  few  predecessors.  This  agree- 
ment in  the  opinion  expressed  about  the  Mammalia 
dates  from  the  earliest  times,  and  is  founded  upon 


2  THE  MAMMALIA. 

the  high  estimation  in  which  man  holds  himself, 
an  opinion  which  we  meet  with  as  uniformly.  Man 
finds  himself  bound  hy  every  fibre  within  the  group 
of  the  Mammalia ;  and  as  soon  as  he  makes  him- 
self the  standard  by  which  to  measure  the  value 
and  the  position  of  living  creatures — and  this  he  has 
every  reason  to  do  within  the  circle  of  those  he  is 
acquainted  with — he  cannot,  when  making  a  com- 
parative survey,  do  otherwise  than  class  them  as 
they  always  have  been  classed. 

The  very  obvious  fact  of  the  close  affinity  of 
the  Mammalia  with  man,  and  the  consequent  neces- 
sity for  some  systematic  arrangement  of  them,  leads 
to  the  further  observation  that  certain  groups  or 
classes  of  animals  resemble  the  Mammalia  in  the 
main  characteristics  of  form  and  structure  more  than 
others.  Nor  has  there  ever  been  any  doubt  as  to 
this  close  'relationship.'  Ever  since  the  days  of 
Aristotle  men  have  been  agreed  about  the  group 
of  the  Vertebrates,  and  about  the  succession  of 
Fishes,  Amphibians,  Reptiles,  Birds  and  Mammals. 
This  order  was  naturally  meant  to  express  the  gra- 
dation of  perfection,  and  always  with  the  supposi- 
tion of  the  ideal  to  be  attained  in  man.  Hence  the 
vertebrates,  as  a  whole,  formed  the  chief  main  divi- 
sion, the  highest  type  of  the  animal  kingdom. 


THEIK  POSITION  IN  THE  ANIMAL  KINGDOM.       3 

The  position  of  the  Mammalia  in  their  connec- 
tion with  the  other  classes  of  vertebrates,  and  their 
special  relationship  with  one  class  of  them — taking 
the  word  relationship  without  its  explanation  by 
descent — rendered  the  old  system  extremely  obscure, 
for  the  facts  themselves  spoke  very  imperfectly. 
The  anatomical  resemblance  is  nowhere  so  absolutely 
distinct  that  the  descriptive  method  could  point  to 
the  bird,  or  to  any  one  of  the  vertebrates,  as  show- 
ing the  closest  and  most  numerous  affinities  with 
the  Mammalia.  That  animals  of  the  frog  species 
and  mammals  should  possess  two  condyles  at  the 
back  of  the  head  as  the  first  vertebras  of  the  neck, 
and  that  birds,  like  lizards  and  their  relatives,  had 
only  one,  always  seemed  surprising  to  comparative 
anatomists.  Yet  what  was  to  be  done  with  this 
and  other  similar  facts  ?  We  know  that  since  the 
middle  of  the  eighteenth  century  the  idea  of  descent 
and  development  flickered  up  here  and  there.  But 
the  theory  was  unable  to  rise  above  the  general 
conception,  and  even  in  the  present  century  its 
importance  was  not  felt  by  an  anatomist  who,  in 
my  opinion,  nevertheless  possessed  the  clearest 
ideas  of  the  connection  between  the  present  and  the 
past.  I  refer  to  the  elder  d' Alton.  Although  his 
interest  in  the  subject  was  aroused  by  Goethe,  it 


4  THE  MAMMALIA. 

was  Goethe  again  who  is  indebted  to  d' Alton  for 
some  of  his  most  frequently  quoted  opinions. 
Goethe,  in  order,  as  it  were,  to  keep  off  the  prof unum 
vulgus,  gives  in  a  mystic  form  what  d' Alton  stated 
unequivocally.  D'Alton's  famous  work  on  skeletons 
also  induced  Goethe  to  discuss  the  subject  of  adapt- 
ability, and  to  maintain  that  adaptation  was  one 
of  the  most  important  factors  in  producing  new 
forms.  *  The  animal  is  formed  by  circumstances 
for  circumstances.' 

The  power  of  an  organism  to  accommodate 
itself  to  the  place  of  its  abode  and  food — which  is 
an  undisputed  phenomenon — must  be  all  the  more 
striking  the  more  complicated  the  structure  of  the 
group  of  animals,  and  can  therefore  generally  be 
more  easily  verified  in  the  case  of  the  mammal, 
even  by  the  unpractised  eye.  As  the  mammal,  in 
the  first  place,  endeavours  to  satisfy  its  need  of 
food,  the  variation  called  forth  by  the  adaptation 
directed  towards  this  want  is  expressed  at  first  by 
its  instruments  of  locomotion  and  mastication.  It 
may  also  be  said  that  mammals  give  more  proof  of 
the  power  of  adaptation  in  the  systematic  arrange- 
ment of  their  parts  than  most  of  the  other  classes 
of  animals,  but  we  must  not  forget  that  this 
arrangement  of  parts,  in  all  classes  of  animals,  is 


THEIR  POSITION  IN  THE  ANIMAL  KINGDOM.      5 

almost  exclusively  the  result  of  adaptation.  The 
power  of  the  animal  to  move  in  accordance  with 
the  peculiarity  of  the  place  of  its  abode,  to  secure 
its  food,  and  to  rear  its  offspring,  is  in  most  cases 
so  perfect  (if  the  imperfections  are  concealed)  that 
the  real  purpose  would  seem  to  be  the  harmony  of 
the  surroundings  and  means  of  subsistence  of  the 
organism.  The  scientific  novice  as  well  as  the 
dualistic  philosopher  finds  '  a  purpose  in  nature ' — 
a  common  purpose  of  connected  systems  of  organs 
— even  where  the  scientific  inquirer  sees  a  number 
of  imperfections,  that  might  more  consistently 
with  a  *  purpose '  have  been  avoided  had  the 
natura  naturans  wished  to  take  a  more  direct  road. 
How  precarious  this  idea  of  a  '  purpose  in  nature  ' 
is,  as  regards  our  own  bodies,  might,  we  think, 
be  felt  with  every  cold  in  the  head.  It  is  only 
when  the  adaptability  has  become  an  actual  con- 
dition that  the  result  appears  to  be  a  preordained 
purpose. 

Those  who  regard  the  Mammalia  as  organisms 
adapted  for  some  special  purpose,  and  exactly  in 
their  place  when  and  as  we  find  them,  are  satis- 
fied with  a  systemative  manual  on  the  subject. 
But,  we  ask,  is  this  kind  of  knowledge  science? 
Does  this  knowledge  give  us  any  real  understand- 


THK 

UNIVERSITY 


OF   THK 


6  THE  MAMMALIA. 

ing  of  the  subject?  Can  those  who  know  the 
Mammalia  of  our  day,  in  all  the  various  phe- 
nomena of  their  life  and  the  differences  in  their 
structure,  be  said  to  be  fully  enlightened  as  to  the 
causes  and  connection  of  all  these  facts  ?  As  this 
has  generally  been  taken  for  granted,  zoology  has 
hitherto  been  stigmatised  by  the  senseless  appella- 
tion of  '  a  descriptive  science ; '  for,  in  fact,  it  was 
not  considered  to  possess  the  character  of  a  science 
that  inquires  into  a  causal  connection.  As  if  a 
science  could  exist  without  having  an  observing  as 
well  as  a  descriptive  part ! 

The  descriptive  zoologist  need  not  in  any  way 
trouble  himself  or  be  astonished  at  anything. 
When,  however,  he  has  to  take  into  consideration 
the  scientific  results  of  recent  times,  he  will  have 
to  pause  before  a  series  of  specially  striking  phe- 
nomena. This  will  happen,  for  instance,  when  he 
is  about  to  make  a  preliminary  comparison  of  the 
Mammalia  with  the  rest  of  the  Vertebrates,  for  he 
will  want  transition  forms  between  the  former  and 
the  latter.  Buffon's  opinion,  that  by  carefully 
observing  two  organisms,  however  different,  an  un- 
interrupted series  of  transition  forms  will  always 
be  found,  did  not  long  hold  good  in  face  of  our 
more  strict  systematic  arrangement.  The  link 


THEIR  POSITION  IN  THE   ANIMAL  KINGDOM.      7 

between  the  Mammalia  and  the  rest  of  the  verte- 
brates has  scarcely  been  looked  for  anywhere, 
except  among  the  birds,  owing  to  the  obviously 
high  degree  of  mental  development  attained  by 
certain  members  of  this  class,  owing  to  the  stronger 
and  more  perfect  circulation  of  their  blood.  But 
neither  Buffon  or  any  other  later  comparative 
anatomist  has  undertaken  to  give  any  specific  proof 
of  this  link,  because,  as  was  said  above,  other 
circumstances  pointed  to  a  relationship  with  the 
Amphibians. 

It  will  not  be  necessary  to  make  other  vain 
attempts  to  bridge  over  the  gap  between  the 
Mammalia  and  the  other  vertebrates  of  the  present 
day.  It  will  even  be  shown  that  this  difficulty  is 
not  at  all  or  but  little  removed  by  our  present 
knowledge  of  primeval  times. 

More  striking  still  are  the  numerous  isolated 
forms  within  the  class  of  the  Mammalia  themselves. 
|The  best  known  example  of  this  kind  of  an  isolated 
form  of  mammal  is  the  horse  and  its  relatives,  the 
genus  EquusJ  The  descriptive  zoologist  places  it  by 
the  side  of  the  two-hoofed  animals.  Yet  the  differ- 
ence between  the  one-toed  horse  and  the  two-toed 
oxen  and  stags  remains  completely  unexplained. 
Besides  this,  the  more  perfect  dentition  of  the  horse 


8  THE  MAMMALIA. 

stands  in  sharp  contrast  with  the  reduced  dentition 
of  most  of  the  ruminants,  which  lack  the  upper 
incisors ;  the  only  point  of  connection  would  seem 
to  be  the  camel,  which  again  has  a  much  fuller 
dentition.  Nevertheless,  the  horse  remains  a  phe- 
nomenon so  peculiar  within  itself,  that  descriptive 
zoology  has  always  classed  the  genus  Horse — which 
is  limited  to  a  few  species — in  the  order  of  the  two- 
hoofed  animals,  which  contains  a  number  of  different 
genera  and  several  hundred  species. 

It  is  much  the  same  with  the  perfectly  unten- 
able order  of  the  many-hoofed  or  thick-skinned 
animals,  for  it  is«made  to  comprise  entirely  different 
members.  What  a  peculiar  form,  for  instance,  we 
have  in  the  elephant  among  the  thick-skinned 
animals,  or,  indeed,  among  the  whole  class  of 
Mammalia:  a  strict  vegetarian,  and  yet  in  every 
respect  an  oddity  among  the  plant-eaters.  The 
caps  of  horn,  somewhat  like  nails,  which  cover 
the  points  of  his  toes,  can  scarcely  be  called  hoofs. 
The  form  of  his  skull,  his  teeth  and  his  trunk,  in 
like  manner,  separate  him  from  all  the  other  plant- 
eaters  in  whose  society  he  has  figured  since  the 
days  of  Linnaeus.  But  even  among  the  rest  of  the 
so-called  many-hoofed  animals  there  is  no  unity, 
even  according  to  the  interpretation  of  a  later, 


THEIE  POSITION  IN  THE  ANIMAL  KINGDOM.       9 

post-Linnsean  system ;  for  the  various  genera  differ 
more  from  one  another  in  structure,  feet  and  teeth, 
than  do  the  members  of  other  orders.  That  the 
pig  shows  more  affinity  with  the  rhinoceros  or  with 
the  hippopotamus  than  with  the  ox,  is  anything 
but  self-evident  as  soon  as  it  is  clearly  perceived 
that  the  connecting  link  cannot  be  in  the  number 
of  hoofs.  We  may  mention  as  isolated  genera  also 
the  camel,  the  giraffe,  and  the  fingered-animals ; 
and  as  isolated  families  all  those  animals  which,  on 
account  of  their  defective  dental  arrangement,  may 
be  classed  as  animals  poor  in  teeth  (Edentata), 
such  as  sloths,  girdled  animals,  ant-eaters,  and 
scaled  ant-eaters;  for  even  as  groups  they  show 
among  one  another  a  want  of  harmony  similar  to 
that  of  the  heterogeneous  divisions  of  the  class  of 
the  many-hoofed  animals.  If,  further,  we  draw 
attention  to  the  contrast  in  which  the  Marsu- 
pials stand  to  all  the  other  orders  of  mammals, 
while  they  differ  very  widely  among  themselves, 
we  shall  have  pointed  out  a  large  number  of 
phenomena  that  are  wholly  unintelligible  by  them- 
selves. 

In  addition  to  this  we  meet  with  the  many 
geographical  difficulties ;  for  instance,  the  geo- 
graphical distribution  of  animals  which,  by  itself, 


10  THE  MAMMALIA. 

is  inexplicable.1  Certainly  all  the  phenomena  here 
referred  to  are  intelligible  when  the  supposition  of 
migration  does  not  stumble  upon  contradictions 
and  surmountable  obstacles,  and  when  the  capacity 
of  the  organism  to  acclimatise  itself — using  the 
word  in  its  widest  sense — is  taken  into  account  as 
a  long  since  established  fact;  but  the  question  as 
to  the  origin  of  species  in  general  is  left  as  a  point 
to  be  considered  apart.  Without  doubt  that  which 
tends  to  the  widest  distribution  of  an  animal  form 
and  to  the  intercourse  between  the  most  different 
species,  is  the  sea.  Since  recent  scientific  investi- 
gations have  made  us  as  intimately  acquainted 
with  the  ocean-currents  as  with  the  systems  of 
rivers,  with  the  range  of  cold  currents  and  tongues 
qf  water  in  the  southern  seas  and  conversely,  and 
has  marked  the  different  depths  of  the  ocean 
currents,  and  given  us  charts  of  the  bottom  of 
the  sea,  with  maps  showing  its  elevations  and 
depressions — it  would  seem  that,  with  an  account 
of  the  animals  in  the  sea,  the  possibilities  and 
causes  of  their  occurrence  would  likewise  be  ex- 
hausted. 

The  state  of  the   matter  is  very  different   as 
regards  the   distribution   of  animals   on   land,  in 

1  Wallace,  The  Geographical  Distribution  of  Animals. 


THEIR  POSITION  IN   THE  ANIMAL  KINGDOM.      11 

lakes  and  rivers.  Of  a  large  number  of  inland 
lakes  we  know  that  it  is  only  within  a  period 
scarcely  separable  from  the  present  that  they  have 
become  detached  from  the  sea.  A  large  portion  of 
the  inhabitants  of  these  lakes  is  accounted  for  by 
this  very  fact.  In  regard  to  the  rivers  we  have 
here  specially  to  consider  fishes  and  mussels.  Now 
it  is  well  known  that  a  number  of  fishes— for 
instance,  the  salmon,  smelt,  eel,  and  certain  kinds 
of  plaice — spend  their  life  partly  in  fresh  and  partly 
in  salt  water,  according  to  the  season  of  the  year, 
for  the  sake  of  propagation  ;  and  further,  that  they 
can  be  transferred  from  the  one  to  the  other  kind 
of  water  without  injury.  Hence  we  may  assume, 
in  the  case  of  all  purely  fresh-water  fishes  and 
mussels,  that  their  progenitors  could  also  at  one 
time  live  in  either  kind  of  water  :  we  have  thus  a 
perfectly  satisfactory  explanation  of  the  occurrence 
of  the  same  genera,  partly  also  of  the  same  species, 
in  rivers  situated  very  far  apart.  Examples  of 
this  kind  in  the  group  of  mammals  are  not  fre- 
quent, but  instructive.  The  sea-cow,  discovered 
by  Vogel  in  the  Benue,  is  the  only  species  of  the 
order  of  the  Sirenia  which,  it  would  seem,  has 
never  attained  a  fuller  development,  and — to  use 
an  expression  of  Kiitimeyer's — has  completely  taken 


12  THE  MAMMALIA. 

leave  of  the  sea.  On  the  other  hand,  the  American 
lamantin  is  still  undergoing  the  transition,  and 
feels  as  comfortable  in  the  sea  as  it  does  in  the 
lowest  currents  of  large  streams.  The  dugong  of 
Eastern  Africa  has,  however,  remained  perfectly 
faithful  to  its  old,  habitual  element.  An  interest- 
ing example  of  the  occurrence  of  a  mammal  in  an 
inland  lake  is  the  dog-fish  of  the  Caspian  Sea.  It 
was,  in  fact,  simply  left  there.  That  this  large 
sheet  of  water  was  at  one  time  connected  with  the 
sea  is  a  long  since  established  fact. 

By  this  remark,  and  a  return  to  the  geological 
past  (even  though  it  be  to  a  most  recent  past),  we 
have  again  entered  the  only  path  which  leads  to 
the  understanding  of  all  the  geographical  configu- 
rations of  the  present,  more  particularly  to  the 
distribution  of  the  organisms,  and  above  all  to  that 
of  the  land  animals.  The  difficulty  of  meeting 
with  closely  related  species,  orders,  and  larger 
groups,  in  regions  lying  far  apart  and  separated 
by  high  chains  of  mountains  or  impassable  oceans, 
has,  since  Buffon's  days,  been  quietly  settled  with 
the  word  '  vicariate,'  which  proves  anything  but  a 
true  understanding  of  the  matter.  When  it  is  said 
that  the  Marsupials  '  vicariate '  in  Australia  for  the 
other  groups  distributed  on  the  other  continents, 


THEIR  POSITION  IN  THE  ANIMAL  KINGDOM.       13 

this  expression  denotes  nothing  but  the  bare  fact, 
nothing  but  the  mere  statement,  that  in  America 
we  do  not  meet  with  the  camel  but  with  the  llama, 
which  in  a  few  main  characteristics  shows  some 
affinity  with  it.  The  one  '  vicariates '  for  the 
other.  Why  ?  we  ask.  What  is  the  meaning  of 
such  *  vicariating  '  ?  We  get  no  answer. 

Now,  in  raising  the  study  of  zoology  from  the 
stage  of  a  mere  descriptive  method  to  the  height 
of  a  true  science,  we  demand  an  explanation  of 
connections  and  agreements.  Every  endeavour 
to  comprehend  the  animal  world,  from  a  scientific 
point  of  view,  makes  modern  geology  the  basis  of 
its  operations,  and  its  testimony — which  is  of  fifty 
years'  standing — is  that  the  present  condition 
of  the  earth's  surface,  the  distribution  of  land  and 
water,  has  proceeded  from  the  most  gradual  and 
primeval  processes,  except  in  cases  of  purely 
locally  interrupted  transformations.  Scientific 
study  must,  secondly,  accept  the  phenomenon  of 
the  power  of  adaptability  in  organisms,  that  ver- 
satility of  the  organs  with  which  plants  and 
animals  meet  the  variability  of  their  external 
circumstances,  and  adapt  themselves  to  changes 
that  are  taking  place,  by  habit  and  by  the  gradual 
changes  of  their  own  bodies  which  are  connected 


14  THE  MAMMALIA. 

with  it.  Whoever  believes  in  the  unity  of  the 
human  race  must  be  a  decided  advocate  of  this 
variability,  even  though  it  be  but  in  the  crude 
notion  of  regarding  the  negroes  as  sun-burnt 
white  men,  and  the  latter  as  bleached  black  men. 
Those,  however,  who  feel  convinced  of  the  contrary 
maintain  the  variability  to  be  the  result  of  the  un- 
doubted mixing  of  the  races  and  species. 

If  we  look  upon  the  dog  as  having  been  created, 
then  the  assumption  of  an  extraordinary  capacity 
of  adaptation  is  unavoidable,  but  it  is  equally  so 
to  those  who  see  in  the  domestic  dog  a  number 
of  different  species  of  tamed  jackals. 

THE    PHENOMENA   OF    CONVERGENCE. 

Even  Goethe  early  recognised  the  fact  that  ex- 
ternal influences — '  the  four  elements  ' — to  which 
the  animal  has  to  submit  and  to  adapt  itself  for 
the  necessity  of  self-preservation,  change  the  form 
and  mode  of  life  to  so  great  an  extent  that  re- 
semblances have  been  produced  between  creatures 
wholly  different  at  first.  But  Goethe  did  not  give 
unequivocal  expression  to  this  thought  till  d'Alton 
had  very  clearly  emphasised  the  transformation 
and  development  of  organisms,  as  the  result  of 
*  elementary  conditions.'  A  number  of  Goethe's 


PHENOMENA  OF  CONVERGENCE.  15 

remarks,  which  are  continually  being  quoted  since 
Haeckel's  enthusiastic  advocacy  of  Goethe  as  the 
precursor  of  Darwin,  are  mere  transcriptions  of 
passages  from  d' Alton.1  The  phenomenon  that 
different  animals,  very  divergent  in  their  struc- 
ture, and  hence  not  related  to  one  another,  can, 
when  placed  in  the  same  circumstances,  develop 
certain  similarities,  did  not  escape  his  thoughtful 
mind.  He  writes:  'The  Eodents  in  form  show 
affinity  with  various  orders ;  the  rat  resembles 
the  beast  of  prey ;  and  the  hare  in  its  mode 
of  life  and  food,  even  in  form  and  characteristics, 
resembles  the  Ruminants.'  This  sentence  Goethe 

1  Goethe's  poem,  the  Metamorphosis  of  Animals,  where  we 
find  the  lines— 

Hence,  each  form  conditions  the  life  and  acts  of  the  creature, 
And  each  fashion  of  life,  with  reflex  forcible  action, 
Works  on  the  form  ; 

Also  hestimmt  die  Gestalt  die  Lehensweise  des  Thieres, 
Und  die  Weise  des  Lebens,  sie  wirkt  auf  alle  Gestalten 
Machtig  zurttck— 

belongs  to  the  year  1819.  D'Alton,  in  his  work  on  the  Skeletons 
of  the  Eodents  in  1823,  says  :  '  Thus  it  can  no  longer  appear 
doubtful  that  the  tendency  of  development  in  the  organism  is  as 
dependent  upon  outward  circumstances,  as  the  mode  of  life  of 
animals  is  determined  by  their  organisation.'  This  thought, 
like  others,  is  reproduced  by  Goethe  when  discussing  this 
classical  work  in  1824.  In  this  '  intellectual  discourse  '  he  may 
have  found  to  his  great  satisfaction  what  he  had  himself  long 
since  perceived  and  pondered  over. 


16  THE  MAMMALIA. 

transcribes  in  his  own  way  with  a  seemingly  unim- 
portant alteration,  which,  however,  changes  the 
matter  itself  essentially.  He  says :  *  However  much 
the  form  of  the  Eodent  may  vary  to  and  fro, 
apparently  knowing  no  boundary,  still  in  the  end 
it  is  found  confined  within  the  genera1  animal 
type,  and  must  approximate  either  the  one  or  the 
other  group  of  animals ;  and  thus  it  inclines  both 
to  the  beasts  of  prey  as  well  as  to  Kuminants,  to 
apes  as  well  as  to  bats,  and  even  to  other  inter- 
mediate groups.' 

These  similarities  and  parallelisms  did  not 
receive  much  attention  until  Darwin's  day.  Darwin 
himself  speaks  of  convergence  only  casually,  and  by 
way  of  pointing  out  the  great  improbability  of  its 
occurrence  as  the  cause  of  agreements  in  organisms 
not  related  by  blood.  But  for  the  last  ten  years 
or  more,  zoologists  have  so  often  been  forced  to 
account  for  the  existence  of  similarities  and  agree- 
ments— not  as  inherited  peculiarities  of  race,  but 
as  transformations  and  assimilations,  the  result  of 
outward  circumstances  upon  the  same  or  similar 
original  forms — that  this  agency  must  be  taken 
into  consideration,  and  will  be  specially  necessary 
in  our  present  inquiry,  for  it  seems  to  have  played 
no  small  part  in  the  group  of  the  Mammalia.  A 


PHENOMENA  OF  CONVERGENCE.  17 

few  remarks  upon  the  origin  of  the  idea  of  con- 
vergence will,  therefore,  not  be  out  of  place. 

As  soon  as  the  idea  has  been  grasped  that 
mechanism  governs  an  organism  with  the  same 
regularity  as  it  does  an  inorganic  body,  the  ques- 
tion must  naturally  arise  how  far  the  living  sub- 
stratum can  be  influenced  by  outward  circum- 
stances, and  how  far  the  same  results — independent 
of  one  another — may  be  attained  under  the  same 
and  similar  conditions.  The  genius  of  Diderot 
comprehended  the  problem  in  its  widest  applic- 
ability. In  a  conversation  with  d'Alembert  in  1769, 
he  makes  the  latter  start  the  supposition  that 
after  the  destruction  of  all  life  by  the  extinction  of 
the  sun,  a  repetition  of  the  development  of  the 
plants  and  animals  that  formerly  existed  would 
recommence  with  the  rekindling  of  the  heavenly 
body  which  diffuses  force  and  life.  For,  he  adds, 
nothing  else  is  conceivable  but  that  the  causes, 
once  again  set  in  motion,  should  produce  the  same 
effects  as  they  had  already  done.  According  to  the 
Linnaean  and  Cuvier's  interpretation  of  species, 
this  idea  could  scarcely  expect  to  find  acceptance, 
and  it  is  self-evident  that  any  agreement  was  made 
to  rest  upon  the  same  origin  of  the  individuals  of 
the  species,  and  further  upon  the  same  fundamental 


18  THE  MAMMALIA. 

form,  that  is,  upon  the  inexplicable  sovereignty  of 
the  idea  of  type.  Even  though  parallel  groups — 
such  as  the  repetition  of  different  orders  of  the 
Mammalia  within  the  group  of  Marsupials,  the 
repetition  of  the  habitus  of  the  .Rodents  in  the 
Insectivora — were  observed  and  discussed,  still  the 
contented  zoologist  did  no  more  than  enter  these 
observations  into  his  book;  and  remarks  such  as 
those  made  by  Goethe  and  d' Alton  remained  with- 
out result.  What  position  Darwin  took  as  regards 
the  idea  of  convergence,  has  already  been  stated. 
His  school,  too,  endeavoured  at  first  to  account  for 
the  homologies  exclusively  by  inheritance,  and,  on 
the  other  hand,  regarded  the  effects  of  adaptation 
almost  wholly  as  differentiation.  Even  that 
extremely  interesting  adaptation  as  a  means 
of  defence — mimicry — and,  moreover,  the  ease 
where  the  species  in  danger  finds  immunity  and 
protection  in  feigning  a  resemblance  with  the 
species  not  endangered,  did  not  lead  to  any 
generalisation  of  the  inquiry.  Still,  some  striking 
phenomena  of  convergence  were  observed,  and 
others  that  had  long  since  been  known,  but  not 
carefully  considered,  were  inquired  into  more 
particularly.  Among  these  is  Fritz  Miiller's 
admirable  analysis  of  the  arrangements  by  which 


PHENOMENA  OF  CONVERGENCE.  19 

the  land  crabs  of  the  most  different  families  con- 
verge in  their  mode  of  life  and  physiology  of 
breathing.  The  transition  from  life  in  water  to 
life  on  land  has  commenced  in  the  one  and  the 
other  species,  here  and  there,  and  they  meet  in  the 
most  different  stages  of  capacity  for  life  on  land  ; 
no  form  is  so  far  changed  that  its  relation  to  some 
definite  family  is  not  unquestionably  evident.  The 
transition  from  a  life  in  water  to  one  on  land  has 
transformed  both  feet  and  gills,  but  has  not  gone  so 
far  as  to  show  agreement  or  apparent  homology. 
In  this  case  of  convergence  the  mode  of  life  has 
remained  the  same  as  that  in  which  the  Eodents 
resemble  the  Insectivora  and  the  Cetacea  the 
Sirenia.  They  were  judged  differently  without 
principle  or  consistency.  The  agreements  in  the 
Insectivora  and  the  Kodents  had  always  been 
considered  as  accidental  and  purely  external, 
whereas  the  Cetacea  and  Sirenia  were  classed 
together  in  one  order  as  close  relatives. 

We  must  here  mention  an  attempt  made  by 
Kolliker,1   an  eminent  German  scientific   man,  to 

1  Kolliker's  Alcyonaricn  in  the  Abhandlungen  der  SencJcen- 
bergischen  naturforschendew  Gesellschaft,  vii.,  viii.  Published 
separately  under  the  title  of  Morphologie  und  Entwickelungs- 
geschichte  des  Pennatulidenstammes  nebst  allgemeinen  Betrach' 
tungen  zur  Descendenzlehre.  Frankfurt  a.M.,  1872. 


20  THE  MAMMALIA. 

prove  the  theory  of  descent  as  improbable  and  un- 
necessary, by  assuming  in  its  place  a  general  law 
of  development  by  which  the  different  species  origi- 
nated side  by  side  without  blood-relationship.  His 
fundamental  idea,  as  he  himself  says,  is  that  with 
the  first  origin  of  organic  matter  and  of  organisms 
a  plan  of  development  was  also  given,  a  whole 
series  of  possibilities  (by  whom  ?  we  ask),  but  that 
various  outward  influences  acted  determinatively 
upon  individual  development  and  produced  a  dis- 
tinct character.  That  organic  nature  is  the  result 
of  some  grand  plan  of  development  and  of  universal 
laws,  and  that  the  explanation  of  the  processes  of 
development  is  nothing  more  than  that  they  take 
place  according  to  internal  causes,  according  to 
laws  by  which  the  organisms  are  most  distinctly 
forced  to  an  ever  higher  form  of  development.  In 
like  manner  eggs  and  germ  cells  are  said  to  pass 
into  new  forms  from  internal  causes :  indepen- 
dent, living,  youthful  forms  are  said  to  begin  a 
development  different  to  the  typical  one,  while  out- 
ward influences  affect  the  process  in  various  modi- 
fying ways,  and  transformations  ensue  which, 
although  contained  in  the  general  plan,  did  not  all 
necessarily  need  to  be  fulfilled.  Every  different 
species  is  said  to  have  originated  in  this  way  by  it- 


PHENOMENA  OF  CONVERGENCE.  21 

self:  further,  that  it  would  even  seem  probable  that 
one  and  the  same  species  appeared  in  different  pedi- 
grees ;  for,  owing  to  the  unavoidable  assumption  of 
universal  laws  of  formation,  it  cannot  be  denied 
that  the  same  primary  forms  might,  under  certain 
conditions,  be  able  to  lead  to  the  same  final  form. 
Where  individual  species  have  been  found  in  places 
widely  separated,  Kolliker  even  considers  it  more 
appropriate  to  assume  an  independent  origin  for 
them. 

In  the  remarks  just  quoted  there  is  clearly  a 
question  about  development,  even  of  a  plan  of 
development,  but  there  is  no  mention  whatever  as 
to  how  we  are  to  conceive  those  laws  and  effects 
which  have  produced  the  numerous  branches  of  the 
animal  kingdom;  for  what  are  these  internal  causes 
which  so  distinctly  force  things  towards  an  ever 
higher  form  of  development  ?  Nothing  is  to  be 
gained  from  this  idea,  which  scarcely  deserves 
the  name  of  an  hypothesis.  It  is  a  complete  re- 
habilitation of  dualism  and  teleology.  Kolliker's 
supposition  does  certainly  touch  upon  our  present 
views  of  convergence,  but  it  goes  no  further ;  for, 
in  the  first  place,  it  takes  for  granted  the  existence 
of  some  plan  which  cannot  be  accurately  denned, 
a  tendency — i.e.  a  purpose  ;  and,  secondly,  it  does 
4 


22  THE  MAMMALIA. 

not  consider  the  difficulties  arising  from  the  endless 
recurrence  of  the  agreement  of  thousands  of  cir- 
cumstances which  are  necessary  for  the  production 
of  a  definite  organism,  but  declares  this  highly 
improbable  combination  to  be  a  law.  That  a  sea- 
feather  of  the  southern  ocean  should  '  originate ' 
spontaneously  without  ancestors,  and  be  precisely 
like  an  individual  in  the  northern  ocean,  which 
owes  its  existence  to  the  same  unknown  processes 
without  ancestors,  shows  such  a  degree  of  improba- 
bility that  it  amounts  to  an  impossibility.  It  is,  in 
fact,  as  improbable  as  that  Adam  originated  out  of 
a  clod  of  earth.  The  prophecy  that  the  whole 
edifice  of  the  Darwinians  would  collapse,  while  the 
theory  of  a  universal  law  of  development  (which 
assumes  a  number  of  independent  pedigrees  as  its 
basis)  would  rise  up  triumphantly  instead,  has  not 
yet  been  fulfilled. 

However,  convergencies  and  repetitions  have 
been  observed  in  abundance  since  then.  In  my 
work  on  the  Sponges,  I  have  adduced  special  proofs 
of  how  a  series  of  convergencies — the  formation  of 
water-channels,  form  and  disposition  of  microscopic 
bits  of  skeleton  and  entire  skeletons,  root-like  off- 
shoots, tensions  and  other  formations— which  are 
defensive  arrangements  against  the  intrusion  of 


PHENOMENA  OF  CONVERGENCE.  23 

foreign  bodies,  in  short,  characteristics  which  would 
seem  to  justify  the  conclusion  of  relationship,  are 
merely  the  result  of  mechanical  contrivances,  of 
the  effects  of  outward  circumstances  upon  hetero- 
geneous organisms. 

That  outward  circumstances  have  co-operated 
helpfully  and  determinatively  in  the  development 
of  symmetrical  animal  forms,  cannot  be  doubted 
by  any  except  those  who  cling  to  their  belief  in  the 
type  theory.  It  follows  from  this  that,  to  a  certain 
extent,  all  organs  appearing  in  pairs  owe  their 
origin  to  convergence.  We  should  further  have  to 
weigh  those  circumstances  where,  in  nearly  related 
organisms,  the  same  organs  vary  on  one  side ;  this, 
for  instance,  occurs  frequently  in  the  pincers  of  the 
Crustacea.  It  is  only  when  starting  from  conver- 
gencies  of  this  kind — which  may  be  called  homoeo- 
genetic,  and,  according  to  general  supposition,  are, 
as  it  were,  self-evident — that  we  can  pass  on  to 
those  phenomena  to  which  the  idea  of  approxima- 
tion is  specially  applied  in  our  day,  the  heteroge- 
netic  cases  of  convergence.  A  shell-less  tropical 
snail,  Onchidium,  has  eyes  on  the  numerous  wart- 
shaped  protuberances  on  its  back.  Semper l  makes 

1  Semper,  Ueber  SeJwrgane  vom  Typus  der  Wirbelthieraugen 
auf  den  Biicken  von  Schnecken.    Wiesbaden,  1877. 


24  THE  MAMMALIA. 

it  appear  extremely  probable  that  these  eyes— of 
different  species  and  individuals — originated  inde- 
pendently of  one  another.  By  connecting  this 
development  with  the  general  characteristics  of  the 
ceils  of  the  upper  skin  and  of  the  protoplasm,  he 
shows  that  this  repeated  formation  of  eyes  must  be 
regarded  as  arising  from  a  simple  foundation.  This 
is  one  form  of  convergence,  repetition  in  the  indivi- 
dual. The  other  is  contained  in  the  fact  that  the 
eye  of  the  onchidium  shows  an  advance  towards 
the  eye  of  the  vertebrate,  inasmuch  as  its  structure 
and  the  retina  differ  essentially  from  the  eye  of  the 
other  molluscs. 

A  few  years  ago  a  great  fuss  was  made  about  a 
case  of  convergence  which  scarcely  deserved  this 
name,  and  when  inquired  into  dwindled  down  to 
certain  superficial  resemblances,  such  as  have  been 
observed  times  without  number  since  we  have  had 
descriptions  of  natural  objects.  I  refer  to  the  re- 
semblance of  certain  primeval  reptiles  to  mammals, 
the  so-called  Theriodonta.  The  case  was  this.1  In 
the  Trias  formation  of  the  southern  extremity  of 
Africa  there  were  found,  in  addition  to  the  colossal 
plant-eating  reptiles  of  the  group  Dinosauria,  a 
series  of  other  animals,  hitherto  unknown,  which, 

1  Owen,  Fossil  Reptilia  of  South  Africa.    London,  1876. 


PHENOMENA  OF  CONVERGENCE.  25 

upon  the  very  first  examination  of  the  teeth,  proved 
to  be  flesh-eaters.  Now  the  teeth  of  the  modern 
flesh-eaters  are  characterised  by  being  definitely 
separated,  and  by  the  peculiar  formation  of  the 
incisors,  the  canines,  and  the  molars.  The  canines 
above  and  below  and  on  either  side  of  the  jaw  are 
powerful  weapons,  and  admirable  instruments  for 
tearing  off  flesh  and  for  the  gnawing  and  the 
breaking  up  of  bones.  They  separate  the  incisors 
from  the  molars  in  a  distinctive  manner. 

In  the  case  of  the  above-mentioned  South 
African  reptiles  also,  the  teeth,  which  from  their 
position  we  know  to  have  been  incisors,  are  sepa- 
rated from  the  molars  by  a  large  canine  tooth.  The 
lower  one  rises  in  front  of  the  upper  one,  yet  when 
the  mouth  is  closed  it  lies  close  to  the  inside  of  the 
upper  jaw.  The  molars  are  certainly  small  and 
cone-shaped ;  however,  when  drawing  a  comparison 
we  can  recall  similar  instances  of  this  in  seals. 
Owen,  to  whom  we  owe  the  description  of  these,  in 
any  case,  very  remarkable  animals,  also  draws 
attention  to  the  formation  of  the  upper  part  of  the 
arm,  which,  apart  from  the  difference  in  the  form- 
ation of  the  extremity  of  the  upper  joint,  shows  an 
approximation  to  the  cat-type  in  the  construction 
of  the  extremity  of  the  lower  joint,  for  the  ulna 


26  THE  MAMMALIA. 

and  the  second  bone  of  the  lower  arm — the  radius. 
Owen  accordingly  makes  the  names  of  the  new 
genera  remind  us  of  the  dog,  wolf,  tiger,  &c., 
Cynodracon,  Lycosaurus,  Tigrisuchus.  He  then 
speaks  of  the  importance  of  the  discovery  and  says : 
'  If  the  gap  in  the  series  of  animals  between  the 
Mesozoic  and  Psychozoic  air-breathers  had  not  been 
filled  up  otherwise  than  by  reptiles,  the  remnant  of 
that  class  which  has  survived  and  reached  our 
times  would  have  testified  to  the  total  loss  of  such 
gains  of  organisation  as  had  enriched  the  ancestors 
and  predecessors  of  modern  tortoises,  lizards,  and 
crocodiles. 

*  We  know  now  that  not  one  of  these  gains  has 
been  lost,  but  has  been  handed  on,  continued  and 
advanced  through  a  higher  type  of  vertebrates,  of 
which  type  we  trace  the  dawn  back  to  the  period 
when  reptiles  were  at  their  best— grandest  in  bulk, 
most  numerous  in  individuals,  most  varied  in  spe- 
cies, best  endowed  with  kinds  and  powers  of  loco- 
motion, and  with  the  instruments  for  obtaining 
and  dealing  with  both  animal  and  vegetable  food. 

'  Has  the  transference  of  structures,  it  may  be 
asked,  from  the  reptilian  to  the  mammalian  type 
been  a  seeming  one,  delusive,  due  to  accidental 
coincidence  in  animal  species  independently  and 


PHENOMENA  OF  CONVERGENCE.  27 

thaumatogenously  created  ?  Or  was  the  transfer- 
ence real,  consequent  on  nomogeny,  or  the  incoming 
of  species  by  secondary  law,  the  mode  and  way  of 
operation  of  which  we  have  still  to  learn  ?  Certain 
it  is  that  the  lost  reptilian  structures  specified,  are 
now  manifested  by  quadrupeds  with  a  higher  con- 
dition of  cerebral,  circulatory,  respiratory,  and  legu- 
mentary  systems — a  condition  the  acquisition  of 
which  is  unintelligible  to  the  writer  on  either  the 
Lamarkian  or  the  Darwinian  hypothesis.' 

It  is  unintelligible  to  us  also,  for  we  do  not 
in  the  slightest  degree  imagine  that  those  coinci- 
dences, which  are  neither  great  nor  astonishing, 
have  to  be  understood  by  means  of  Darwin's  hypo- 
thesis. There  is,  in  fact,  no  question  whatever 
about  transferred  conditions  of  organisation,  for  the 
coincidence  is  confined  to  mere  adaptations,  and, 
in  part,  very  superficial  ones ;  adaptations  which, 
in  some  cases,  are  *  intelligible '  without  any  diffi- 
culty. With  the  help  of  our  present  prototypes 
and  the  above  fossil  material,  we  can  imagine  all 
kinds  of  substitutes  for  our  wolves  and  the  other 
beasts  of  prey.  It  is  extremely  probable  that  many 
of  the  earlier,  and  to  us  unknown  mammals,  in- 
herited a  uniform  set  of  teeth  (perhaps  somewhat 
like  the  dolphin's)  direct  from  their  ancestors  of 


28  THE  MAMMALIA, 

the  amphibian  or  reptile  species.  Now  the  fact 
that  direct  descendants  of  reptiles,  with  a  uniform 
set  of  teeth,  should  acquire  distinctive  corner  teeth 
(canines)  in  consequence  of  their  tearing  their  vic- 
tims, as  is  the  habit  of  beasts  of  prey,  and  that 
certain  mammals  have  acquired  these  teeth  also, 
owing  to  their  having  taken  to  flesh-eating,  is  a 
convergence  that  can  be  most  satisfactorily  ex- 
plained as  the  result  of  the  same  activity  upon 
similar  or  the  same  developments  in  the  earlier 
forms  of  teeth.  It  is,  as  we  have  already  said, 
a  case  of  convergence  of  the  most  superficial  kind. 
Among  living  reptiles— in  the  Hatteria-,  Uromastix 
spinipeSy  and  also  a  species  of  agama — we  meet 
with  advances  towards  the  dentition  of  the  Car- 
nivora.  But  even  when  the  canine  is  followed  at 
first  by  small  pointed  teeth,  and  then  by  broader 
ones,  there  is  nothing,  either  here  or  in  the  case  of 
the  fossil  African  reptiles,  that  can  be  pointed  out 
as  '  peculiar  molars  with  broad  crowns '  ("VVieders- 
heim). 

It  is  self-evident  that  given  a  like  beginning 
and  like  circumstances,  we  will  more  readily  meet 
with  similar  and  the  same  phenomena  than  where 
there  was  inequality  to  start  with.  In  other 
words  homo3ogenetic  convergences  occur  most  fre- 


PHENOMENA.  OF  CONVERGENCE.  29 

quently.  The  Linnsean  conception  of  things,  to- 
gether with  the  idea  of  type,  and  finally  the  more 
recent  idea  of  homology  as  agreement  by  reason 
of  derivation,  have,  however,  been  the  cause  that 
approximations  in  general,  especially  within  the 
given  '  natural  group,'  were  more  or  less  neglected, 
or,  at  least,  that  merely  surmised  homologies — 
such  as  the  breathing  apparatus  of  the  lung-snails 
— turned  out  to  be  convergences.  Within  the 
group  of  mammals  we  meet  with  a  very  evident 
series  of  convergences  which  have  already  been 
spoken  of  above.  Still,  all  circumstances  con- 
sidered, convergence  can  explain  only  the  smallest 
portion  of  the  phenomena.  That  the  Marsupials 
should  show  agreements  with  certain  orders  of  the 
higher  mammals  is,  at  least,  in  part  approxima- 
tion. That  they  form  an  unity  among  one  another 
is  another  thing.  Why  are  cats  and  dogs  classed 
together  as  beasts  of  prey  ?  Why  are  pigs,  oxen, 
and  deer  classed  as  hoofed-animals  ?  In  short, 
setting  aside  the  above  instances,  in  the  other  cases 
of  agreement  convergence  is  improbable  a  priori, 
and  the  explanation  of  all  the  other,  the  main  por- 
tion, must  be  looked  for  in  the  doctrine  of  descent. 
It  contains  the  greater  amount  of  probability,  a 
probability  which  often  borders  upon  certainty. 


30  THE  MAMMALIA. 

And  hence  every  class  of  the  Mammalia  of  the 
present  day  can  be  understood  only  from  its  con- 
nection with  its  geological  ancestors.  But  are  we, 
by  admitting  true  agreement  in  organisms  and  their 
parts,  and  by  only  allowing  what  is  inherited  to  be 
real  homologies,  are  we  entering  a  domain  wholly 
distinct  from  that  of  convergence?  On  the  con- 
trary. Inheritance  is  only  a  case  of  repetition 
under  the  same  conditions,  a  case  of  universal 
law.  The  whole  Darwinian  principle  of  selection 
and  progress  finds  its  application  also  in  the 
generalisation  of  the  doctrine  of  repetitions. 

THE    DISTINCTIVE    CHARACTERISTICS   OF   THE 
MAMMALIA. 

The  earlier  zoologists,  with  Linnaeus,  classed 
together  as  one  species  all  those  individuals  *  that 
agree  in  essential  points  and  have  been  descended 
unchanged  from  the  same  ancestors.'  The  later 
zoologists  replace  this  supposed  straight  line  of 
descent,  which  involves  the  miracle  of  creation 
and  also  the  future  invariability  of  organisms,  by 
including  the  agency  of  variability  dependent  upon 
time  and  circumstances.  As  long  as  animal  beings 
of  a  supposed  or  proved  common  descent  agree  in 
form  and  structure,  we  leave  them  together  as  one 


DISTINCTIVE   CHARACTERISTICS.  31 

species  :  the  idea  is  one  of  most  uncertain  limit, 
and  differs  according  to  the  views  of  each  investi- 
gator. We  know  of  many  species  of  such  stability 
that  the  earlier  definition  would  seem  to  find  its 
application  in  their  case;  but  there  are  others 
again  whose  variability,  indefiniteness,  and  inde- 
finability  have  baffled  all  attempts  at  a  more 
accurate  limitation. 

Species  of  this  kind,  consisting  of  a  mere  suc- 
cession of  forms,  are  now  met  with  principally 
among  the  lower  orders  of  animals ;  for  instance, 
the  Sponges  consist  almost  entirely  of  such  a 
succession  of  forms  which  seem  to  merge  one  into 
the  other.  The  Mammalia,  on  the  other  hand, 
have  in  the  course  of  the  later  geological  periods 
settled  down  more  quietly.  The  days  when  they 
were  undoubtedly  much  more  varied  in  form  than 
now,  and — like  the  lower  orders— developed  almost 
entirely  into  varieties,  are  passed.  In  the  grand 
sifting  process  of  thousands  of  years,  numerous 
forms  have  dropped  off  and  vanished,  and  the 
majority  of  the  mammals  of  the  present  day  might 
lead  one  to  assume  the  stability  of  species. 

The  Mammals  of  to-day  are  sharply  separated 
from  the  other  vertebrates  by  a  series  of  pecu- 
liarities in  structure  and  development.  Even  the 


32  THE  MAMMALIA. 

entirely  changed  mode  of  life  of  the  Cetacea  has 
not  obscured,  or  only  superficially  obscured,  these 
characteristics ;  for  even  the  loss  of  the  hind  limbs 
is  of  subordinate  importance  compared  with  other 
significant  peculiarities  of  the  class,  and  moreover 
the  loss  of  limbs  is  met  with  in  other  classes,  and 
only  shows  to  what  extent  the  members  of  one 
group  may  diverge. 

We  will  mention  one  characteristic  in  the 
skeleton  which  distinguishes  the  whole  group  of 
existing  mammals  from  all  other  vertebrates  :  their 
lower  jaw  is  directly  attached  to  the  skull,  and 
not  by  means  of  the  so-called  '  quadrate  bone.' 
This  bone  is  met  with  from  the  fish  to  the  bird, 
mostly  as  one  of  considerable  size.  Indications 
of  it  occur  also  among  mammals.  The  substance, 
however,  does  not  harden  into  bone  and  become 
the  stalk  of  the  lower  jaw  so  easily  recognised 
in  the  heads  of  birds,  but  is  employed  in  forming 
one  of  the  small  bones  of  the  ear.  Further,  in  all 
of  the  Mammalia  the  chest  and  abdomen  are  sepa- 
rated by  the  diaphragm  or  midriff,  a  muscle  which 
is  exceedingly  important  for  the  mechanism  of 
breathing.  All  the  Mammalia  have  lacteal  glands, 
and  in  the  case  of  most  mammals  the  foetus  is 
attached  to  the  mother  by  a  placenta,  so  that  the 


DISTINCTIVE  CHARACTERISTICS,  33 

nutrition  and  growth  of  the  embryo  do  not  require 
to  be  restricted  to  the  comparatively  small  amount 
of  yolk  in  the  egg,  but,  as  a  rule,  are  derived 
directly  from  the  blood  of  the  mother. 

We  know  of  the  '  quadrate  bone ' — which  in  the 
Mammalia  has  to  a  certain  extent  become  dis- 
placed and  slipped  into  the  skull — from  the  Fishes  ; 
we  see  the  beginnings  of  a  diaphragm  in  the 
Amphibians ;  we  find  various  kinds  of  skin-glands 
(to  which  the  lacteal  glands  belong)  in  all  of  the 
Vertebrates ;  there  is  but  one  step  from  the  distri- 
bution of  the  embryonal  blood-vessels  on  the  so- 
called  allantois  of  reptiles  and  birds,  up  to  the 
formation  of  the  placenta :  these  characteristics  of 
the  Mammalia  are  all  prepared  or  begun  in  the 
lower  classes  of  animals.  But  the  placenta  came 
into  existence  only  with  the  actual  mammals,  and  is 
an  acquisition  towards  a  higher  degree  of  progress. 
But  although  these  characteristics  are  obviously 
inheritances — apart  from  the  last-named  arrange- 
ment, which  was  acquired  only  subsequently—  still 
we  are  absolutely  without  any  transition  forms.  It 
can  only  be  said  that  the  Mammalia  must  have  de- 
veloped from  one  stock,  where  the  characteristics 
of  the  present  Amphibians  (for  instance,  the  two 
occipital  condyles  at  the  back  of  the  head)  were 
5 


34  THE  MAMMALIA. 

allied  with  those  of  the  present  reptiles  (e.g.  the 
allantois).  The  earliest  traces  of  mammals  from 
the  Triassic  rocks  lead  us  to  suppose  a  long  series 
of  predecessors,  and  direct  our  thoughts  to  further 
unfathomed  depths  of  the  earth's  development. 

It  is  a  different  matter  as  regards  those  charac- 
teristics which  the  systematic  zoologist  makes  use 
of,  first  of  all  in  distinguishing  the  subdivisions  of 
the  group,  the  differences  of  the  instruments  of 
locomotion,  more  especially  of  the  outer  limbs, 
hands  and  feet,  and  also  of  the  dentition.  The 
function  of  propagation  exercises  universally  a 
more  subordinate  influence  upon  the  outward 
appearance  and  the  general  habitus  of  the  animal, 
than  does  nutrition.  The  manner  in  which  its 
food  is  acquired  gives  the  organism  its  peculiar 
stamp,  apart  from  the  outer  covering  that  acts  as 
a  protection  against  its  enemies  and  climatic 
changes,  and  varies  accordingly;  and  this  stamp 
is  expressed  chiefly  in  the  formation  of  the  limbs 
and  the  dentition  of  the  mammal.  Cuvier's  words, 
'  Give  me  a  tooth,  and  from  it  I  will  build  up  the 
whole  animal,'  are  to  be  taken  seriously ;  they 
may  be  applied  to  almost  every  other  individual 
part  of  the  skeleton,  and  above  all  to  the  extremi- 
ties of  the  limbs.  The  last  portion  of  a  finger  will 


DISTINCTIVE   CHARACTERISTICS.  35 

often  suffice  to  determine  the  order.  A  whole  toe 
will  give  a  complete  idea  of  the  mode  of  life  and  of 
the  appearance  of  the  primeval  or  still  living 
animal.  In  order,  therefore,  to  obtain  an  insight 
into  the  relationship  and  social  position  of  a 
mammal  form,  we  must  first  of  all  become  ac- 
quainted with  the  foot  of  the  vertebrate  in  its 
simplest  accessible  form,  and  then  examine  the 
different  variations  of  the  mammal  foot  under  the 
supposition  of  direct  transformation.  This  study 
was  undertaken  for  the  first  time  with  perspicuity 
and  success  by  Gegenbauer ;  and  thus  later  modifi 
cations — which  became  specially  necessary,  owing 
to  the  primeval  form  of  fin  of  the  Australian 
Ceratodus— could  perfectly  well  be  explained  in 
connection  with  Gegenbauer's  conclusions  both  by 
himself  and  others. 

The  simplest  form  of  hand  and  foot  is  met  with 
in  the  four-fingered  and  five-toed  Amphibians  and 
various  reptiles,  e.g.  the  tortoises.  Among  the  former 
the  rudiments  of  a  sixth,  sometimes  even  of  a  seventh, 
toe  are  met  with ;  but  with  the  exception  of  these 
few  indications,  and  the  sixth  finger  of  some 
amphibian-like  primeval  animals,  there  are  no 
fossils  relating  to  the  early  history  of  hand  and 
foot,  or  their  transformation  from  the  fish's  fin. 


36 


THE  MAMMALIA. 


On  the  other  hand,  the  five-toed  limh  extends  from 
the  salamander  to  man.  Together  with  this  we 

have  the  most 
various  kinds  of 
disappearances 
and  coalescings 
till  we  reach  the 
one-toed  foot  of 
the  horse,  and 
find,  in  fact, 
that  a  diminu- 
tion in  the  num- 
ber of  fingers 
and  toes  takes 
place ;  never  do 
we  meet  with 
a  restoration 
after  the  de- 
crease, and 
never  with  an 
addition  to  the 
number  of  toes. 
In  order  to 

illustrate  the  fundamental  form,  which  we  shall 
follow  in  its  most  varied  and  interesting  changes, 
let  us  take  the  right  hand  of  a  fresh-water  tortoise 


FIG.   1.— Eight  hand  of  a  river  tortoise. 
Nat.  size. 


DISTINCTIVE  CHARACTERISTICS.  37 

(Clielys  fimbriata)  in  its  connection  with  the  lower 
arm  (fig.  1).  The  two  hollow  bones  of  the  fore- 
arm running  parallel  with  each  other  are  the 
radius  (s)  on  the  thumb-side,  and  the  ulna 
(E).  Then  comes  the  root  of  the  hand,  consisting 
of  nine  separate  little  bones,  to  know  which  in 
detail  is  part  and  parcel  of  the  A  B  C  of  the  study 
of  the  Mammalia.  The  first,  r  (radiate),  lies  close 
to  the  radius,  a  second,  u  (ulnare),  stands  in  the 
same  relation  to  the  ulna.  Between  the  two  is  a 
connecting  bit  i  (intermedium),  and  in  the  curve 
formed  by  the  three  is  the  little  central  bone  c 
(centrale).  The  five  other  parts  of  the  root  of  the 
hand,  1,  2,  3,  4,  5  (carpalia),  belong  each  to  one  of 
the  fingers,  or  rather  to  the  five  parts  belonging  to 
the  middle  hand  (metacarpus),  i,  n,  in,  iv,  v,  before 
the  actual  fingers.  The  foot  with  the  shank  shows 
precisely  the  same  construction  in  number  and 
position  of  the  parts.1  There  would  be  no  need 
to  give  these  names  in  the  example  chosen,  had  not 
the  inquiry  and  naming  proceeded  from  the  anatomy 

Hand  Foot 

1  Radius,  Spoke  Tibia,  Shinbone 

Ulna,  Ell  Perone,  Fibula 
Carpus,  Root  of  the  hand         Tarsus,  Boot  of  the  foot 

Metacarpus,    Middle  of        Metatarsus,  Middle  of  the 

the  hand  Foot 

Digits,  Fingers  Toes. 


38  THE  MAMMALIA. 

of  the  human  subject,  where  the  contrast  between 
hand  and  foot  has  advanced  in  a  very  striking 
manner.  Our  foot  has  remained  an  organ  of  sup- 
port, our  hand  has  become  the  organ  for  grasping. 
The  fibula,  which  corresponds  to  the  ulna,  is 
reduced,  the  tibia  is  the  principal  bone.  The  parts 
of  the  fore  limb  called  the  radiale  and  intermedium 
(r,  i)  have  generally  coalesced  into  the  spring- 
bone  (astragalus),  and  the  bone  of  the  root  of  the 
foot  attached  to  the  fibula — the  ulnare  of  the  hand 
— becomes  the  heel-lone  (calcaneus),  and  is  distin- 
guished by  a  strongly- developed  continuation  at 
the  back ;  the  centrale  exists  as  the  skiff-lone 
(naviculare).  The  first  three  bones  of  the  middle 
foot  are  called  the  wedge-shaped  bones  (1,  2,  3, 
cuneiforme),  the  fourth  and  fifth  bones  of  the 
middle  foot  have  united  and  form  the  cube-bone 
(cuboideum). 

In  accordance  with  this  scheme  we  shall  find 
that  the  different  mammals  show  a  similar  contrast 
in  hand  and  foot — less  in  the  fingers  and  toes 
than  in  the  roots  of  the  hand  and  foot.  It  will  be 
our  endeavour  to  bring  this  subject  prominently 
forward  in  the  course  of  our  discussion. 

It  will  also  be  shown  that  the  dentition  stands 
in  as  close  a  relation  with  the  whole  organisation 


DISTINCTIVE  CHARACTERISTICS  39 

as  regards  form  as  well  as  the  mode  of  life.  The 
study  of  the  teeth  has  acquired  an  entirely  new 
interest  since  Gegenbauer  has  proved  that  the  teeth 
of  sharks  and  rays  are  perfectly  identical  with  the 
scale  and  plate  formations  of  their  outer  skin ;  and 
thus  in  the  case  of  these  fishes  we  can  at  once 
see  the  transition  of  the  outer  hody-skin  into  the 
mucous  membrane  of  the  mouth-cavity,  also  the 
direct  transition  of  the  hard  formation  of  the  skin 
into  movable  teeth.  Oscar  Hertwig  has  given  us 
a  supplement  to  and  a  further  application  of  these 
fundamental  inquiries.  Accordingly,  teeth  have 
originated  from  skin  developments  having  been 
used  for  the  purpose  of  seizing  and  crushing  food. 
In  the  higher  vertebrates  we  are  no  longer  reminded 
of  this  first  origin  of  the  teeth.  We  there  find 
the  adaptation  to  the  new  activity  completed, 
the  organ  has  long  since  come  to  stand  in  a  closer 
relation  to  the  skeleton  as  a  whole.  In  the  case  of 
every  mammal  the  tooth,  in  its  development,  can  be 
traced  to  have  proceeded  from  the  membranous 
covering  of  the  mouth.  And  while  the  capacious 
mouth  and  gullet  of  fishes  has  been  able  in  almost 
every  case  to  cover  itself  with  teeth,  the  Amphibians 
and  Eeptiles  show  a  reduction  in  the  number  of 
teeth  and  of  the  bony  supports,  and  finally  in  the 


40  THE  MAMMALIA. 

mammals  we  find  only  the  actual  jaw-bones  fur- 
nished with  teeth. 

By  this  a  concentration  of  the  tooth-material 
has  been  accomplished,  and  connected  with  it  we  find 
that  concentration  of  force  by  which  the  mammal 
more  readily  and  surely  overpowers  its  living  prey, 
and  prepares  it  for  use  in  the  intestines,  by  mastica- 
tion. In  the  dentition  of  the  mammal  we  have  not 
a  retrogression  but  an  advance  in  the  organisation, 
and  a  further  diminution  in  two  directions  may  be 
expected.  What  has  taken  place  with  numerous 
fishes  has  also  happened  in  the  case  of  some 
of  the  Mammalia  :  under  certain  conditions  of 
nutrition  teeth  have  become  useless  and  have  dis- 
appeared ;  and,  secondly,  the  fuller  number  of 
teeth  of  the  geologically  older  species  has  given 
place  to  a  dentition  less  numerous  but  more 
specialised  in  form  and  action,  and  therefore  more 
advantageous.  As  an  instance  of  the  one  direction, 
we  may  take  the  jaw  of  a  Kuminant,  which  shows 
a  want  of  the  upper  incisors ;  of  the  other  direction 
the  jaw  of  the  Cat  species. 

In  order  to  understand  the  manifold  forms  of 
teeth,  we  must  have  some  knowledge  of  the  develop- 
ment of  the  various  substances  that  form  the  tooth, 
the  origin  of  the  hard  bright  enamel  (ebur),  of  the 


DISTINCTIVE  CHARACTERISTICS.  41 

tooth-bone  (dentine),  which  constitutes  the  principal 
portion  of  the  tooth,  and  of  the  somewhat  softer 
cement  (cementum),  which  serves  in  various  ways 
as  material  for  covering  and  filling.  A  general 
account  will  suffice  for  our  purpose.  The  mem- 
branous covering  of  the  mouth-cavity — like  that 
of  the  outer  skin — consists  of  two  layers,  the  epi- 
thelium (the  upper  skin),  formed  of  several  layers 
of  cells,  and  the  membrane  of  the  cutis  (leather 
skin),  consisting  partly  of  cells  and  partly  of  fibres. 
The  first  sign  of  a  tooth  is  a  knotty  protuberance 
of  the  cells  of  the  epithelium  rising  into  the  cutis. 
Again,  into  this  protuberance  upwards  there  rises 
from  the  cutis  a  cone-shaped  elevation,  upon  which 
there  then  appears  the  first  formation  in  the  shape 
of  a  cap ;  this  is  the  enamel-germ  or  the  enamel- 
membrane  which  produces  the  enamel.  The  other 
portion  belonging  to  the  cutis — i.e.  the  membranous 
tissue  of  cells  which  rises  up  into  the  epithelium 
and  is  termed  the  dentine-germ —  becomes  calcinated 
into  tooth-bone.  But,  in  addition,  the  mem- 
branous tissue  of  cells  directly  connected  with  the 
dentine-germ  produces — in  various  measures  and 
extent — the  fewer-celled  and  softer  cement  round 
about  all  the  immediate  surroundings  of  the  tooth.1 

1  Baume,  Odontologische  Forsclmngen,  I.  Th. ;  published  also 


42  THE  MAMMALIA. 

The  first  indications  of  teeth  are  met  with  at 
a  very  early  stage  of  the  embryo  in  the  gums  that 
are  still  in  the  process  of  forming,  and  these  be- 
ginnings of  teeth  are  then  gradually  enclosed  by 
the  gums.  In  man  and  most  of  the  other  Mam- 
malia during  the  first  years  of  life  we  do  not  find 
the  whole  set  of  teeth  of  their  later  years,  of  their 
mature  age,  nor  indeed  any  such  teeth  as  are  to 
serve  them  throughout  life ;  there  is  at  first  a 
temporary  set  of  teeth,  the  so-called  milk  teeth. 
These  teeth  are  very  like  those  that  replace  them 
subsequently,  the  permanent  teeth,  but  are  smaller 
and  weaker.  ,It  was  an  extremely  interesting  and 
important  discovery  when  Eiitimeyer  proved  in 
detail  that  the  milk  teeth  of  many  of  the  Mammalia 
show  a  greater  agreement  with  their  historical — i.e. 
their  geological  ancestors — than  do  the  permanent 
teeth.  As  a  rule,  for  instance,  in  man  the  first 
set  of  incisors,  canine  teeth,  and  front  cheek- 
teeth are  replaced  by  a  second  set,  and  thus  con- 
stitute the  milk  teeth.  The  teeth  which  replace  the 
milk  cheek-teeth  are  called  premolars,  and  these 

under  the  title  of  Versuch  einer  Entwickelungsgeschichte  des 
Gebisses  (Leipzig,  1882).  This  work  may  be  recommended  as  an 
excellent  one  on  the  subject  and  full  of  suggestive  thoughts, 
even  though  we  may,  at  times,  feel  disposed  to  dispute  some  of 
the  views  put  forward. 


DISTINCTIVE   CHARACTERISTICS.  43 

are  accompanied  by  the  other  back  cheek-teeth,  the 
molars.  But  apart  from  the  fact  that  in  several 
groups  of  mammals — the  whales  and  armadilloes — 
milk  teeth  do  not  occur  at  all  (Owen's  Monophy- 
oclonta),  there  are  among  those  which  do  show  a 
change  of  teeth  (Diphyodonta),  so  many  deviations 
and  exceptions  to  the  rule  that,  as  Baume  has 
proved,  the  prevailing  idea  of  change  of  teeth  as 
a  succession  of  two  distinctly  different  sets,  can 
scarcely  hold  good.  The  origin  of  the  so-called 
milk  teeth  can  be  traced  back  to  the  fact  that  with 
the  shortening  of  the  facial  portion  of  the  skull, 
the  place  for  the  incoming  of  the  tooth-germ 
naturally  became  smaller  as  well,  and  the  germs, 
in  place  of  lying  side  by  side,  came  to  lie  one  above 
the  other.  Hence  those  placed  uppermost  had  to 
be  used  first,  before  the  lower  ones  had  developed 
and  could  uproot  and  finally  expel  their  prede- 
cessors by  pressure.  The  weakening  of  an  indi- 
vidual milk  tooth  or  of  the  whole  set  of  milk  teeth 
will,  accordingly,  in  general  be  a  question  of  time, 
and  depend  upon  the  delay  in  the  development  of 
their  successors.  The  milk  teeth  are  at  a  disad- 
vantage, owing  to  the  inevitably  hostile  position 
which  their  successors  must  sooner  or  later  assume 
towards  them ;  and  they  have  to  face  a  certain 


44  THE  MAMMALIA. 

defeat,  even  though,  in  most  cases,  this  takes  place 
with  the  utmost  slowness.  Instances  of  the  loss  of 
milk  teeth  are  met  with  among  the  Marsupials  and 
seals.  The  whole  phenomenon  belongs  to  the 
chapter  of  '  abbreviated  development.'  It  was  our 
intention  here  merely  to  point  out  this  view  of  the 
subject,  in  order  to  make  use,  in  what  follows, 
of  the  designations  given  to  different  parts  of  the 
jaw,  according  to  position  and  time,  since  Cuvier's 
and  Owen's  classical  investigations.1 

Let  me  here  repeat  that  the  specialisation  of 
the  dentition  frequently  runs  parallel  with  a  speciali- 
sation of  the  limbs.  Thus,  in  comparison  with  its 
geological  ancestors,  the  dentition  of  the  horse  is 
very  specialised,  and  this  is  equally  evident  as 
regards  its  foot,  the  transformation  of  which,  from 
a  five-toed  member — not  specially  suited  either  for 
running,  grasping,  or  climbing — into  a  one-hoofed 
member,  so  admirably  adapted  for  running,  has 

1  Example. — In  man  the  milk  teeth,  the  denies  decidui,  con- 
sist of  the  cutting  teeth  (incisors),  the  canine  or  eye  teeth,  and 
the  two  front  cheek-teeth.  In  addition  to  these  there  are  the 
three  back  cheek-teeth  that  have  no  predecessors.  The  teeth  of  the 
full-grown  man  are  indicated  thus  : — i  \  c  \  p  f  m  |,  i.e.  on  either 
side  above  and  below  two  incisors,  one  canine,  two  premolars 
and  three  molars.  Although  Cuvier  of  course  knew  the  dents 
de  lait  and  the  dents  de  r emplacement,  still  Owen  was  the  first 
rigorously  to  carry  out  the  designation. 


PALEONTOLOGY   SINCE   CUVIER.  45 

been  accomplished  step  by  step.  Thus  we  very 
often,  and  justly,  hear  of  generalised  and  specialised 
animal  forms,  which  show  their  characteristic  and 
contrasting  peculiarities  chiefly  in  those  organs,  the 
extremities  and  the  dentition.  These  differences 
were  perceived  even  by  the  earlier  observers,  and 
were  compared  with  the  embryonal  conditions,  with 
the  development  from  the  general  state  of  the  early 
indications  through  all  the  details  of  the  ripening 
offspring.  The  significance  of  this  point  must  be 
borne  in  mind  when  we  term  the  geological  and 
earlier  forms  as  general  and  embryonal  forms,  and 
the  later  ones  as  the  specialised  forms. 

THE    EXTENSION    OF    PAL.EONTOLOGICAL    SCIENCE 
SINCE    CUVIER. 

The  fact  that  the  theory  of  descent  appears  less 
prominent  during  the  first  half  of  our  century,  and 
is  so  frequently  and  justly  connected  with  Cuvier's 
opposition  to  it,  makes  it  necessary  for  us  to  allude 
to  his  position  in  regard  to  this  great  question. 
Cuvier's  almost  autodidactic  manner  of  working 
and  viewing  things  comprised,  as  is  well  known, 
the  whole  animal  kingdom,  with  the  exception  of 
Borne  groups  of  microscopic  and  other  lower  ani- 
mals. But  he  was  a  specialist,  above  all  things,  in 
6 


46  THE  MAMMALIA. 

the  osteology  of  the  living  and  fossil  Mammalia, 
and  thus  stands  as  the  founder  of  palaeontology  and 
its  comparative  method.  It  was  no  small  advan- 
tage to  Cuvier  that  in  his  immediate  neighbourhood 
were  to  he  found  deposits  of  the  Paris  Eocene,  lime 
and  gypsum,  containing  the  remains  of  the  earliest 
forms  of  mammals.  It  is  astonishing  what  he  accom- 
plished in  his  '  Recherches  sur  les  ossements  fossiles,' 
where  his  principle  of  correlation  is  so  brilliantly 
proved.  The  imperfectly  observed  geological  facts 
and  the  imperfect  discoveries  led  him,  nevertheless, 
to  the  conviction  that  from  time  to  time  sudden  con- 
vulsions, catastrophes,  had  transformed  the  earth's 
crust,  and  destroyed  the  living  creatures,  either 
completely  or  with  the  exception  of  a  small  re- 
mainder ;  he  further  thought  that  those  which  sur- 
vived were  obliged  often  to  seek  a  new  home  far 
from  their  original  abodes.  The  question  as  to 
whence  came  the  new  inhabitants  of  the  succeeding 
peaceful  period,  after  each  of  the  great  murderous 
catastrophes,  Cuvier  settles  in  a  somewhat  cursory 
manner.  '  I  do  not  maintain  that  a  new  creation 
was  required  to  produce  the  present  species ;  I  say 
only  that  they  did  not  live  in  the  same  regions,  and 
that  they  must  have  come  from  elsewhere.'1  This 

1  The  quotation  is  from  Cuvier 's  book  referred  to  above — his 
Becherches  sur  les  ossements  fossiles  (1821). 


PALEONTOLOGY  SINCE  CUVIER.  47 

vagueness  remains  in  spite  of  his  admitting  the 
fact  that  at  one  time  life  began  on  earth.  For, 
according  to  Cuvier,  the  varieties  that  are  depen- 
dent upon  time,  climate  and  domestication,  remain 
within  a  given  boundary,  while  the  species  show 
certain  characteristics  which  resist  every  kind  of 
influence,  and  are  as  little  affected  by  time  as  by 
climate  and  domestication.  Hence  he  directly 
opposes  Lamarck's  theory  of  descent,  i.e.  that  the 
fossil  forms  are  the  ancestors  of  those  of  the  present 
day.  His  main  argument  is  the  want  of  fossil 
intermediate  forms,  '  for,'  he  adds,  *  if  the  species 
had  changed  gradually,  we  should  find  traces  of 
these  gradual  transformations ;  we  should  find  some 
transition-forms  between  the  Palaeotherium  and  the 
species  of  the  present  day,  and  these  have  mean- 
while not  been  met  with.' 

Cuvier  therefore  did  not,  as  many  have  sup- 
posed, hold  fast  to  the  belief  in  a  supernatural  cre- 
ation from  any  preconceived  opinion ;  he  was  more 
disposed  to  leave  the  problem  as  to  the  origin  of 
animal  forms  in  uncertainty,  as  facts  did  not  seem 
to  admit,  meanwhile,  of  any  safe  conclusion.  It  is 
therefore  very  intelligible  that  one  of  Cuvier 's  last 
and  still  living  pupils — the  eminent  palaeontologist 
and  zoologist,  Kichard  Owen — should  straightway 
have  accepted  the  theory  of  natural  descent  (under 


48  THE  MAMMALIA. 

a  special  Divine  direction,  it  is  true),  after  having 
satisfied  himself  personally  as  to  the  existence  of 
intermediate  forms  between  the  Palaeotherium  and 
Horse.  Cuvier,  his  teacher,  had,  however,  not 
the  desired  knowledge  of  these  forms.1 

Since  Cuvier's  day,  i.e.  within  the  last  fifty 
years,  and  more  especially  within  the  last  twenty 
and  twenty-five  years,  our  palaeontological  know- 
ledge as  a  whole,  and  particularly  as  regards  the 
Mammalia,  has  been  so  immensely  extended,  that 

1  Owen,  in  his  Anatomy  of  Vertebrates,  General  Conclusions, 
says :  *  With  this  additional  knowledge,  the  question  whether 
actual  races  may  not  be  modifications  of  those  ancient  races 
which  are  exemplified  by  fossil  remains,  presents  itself  under 
very  different  conditions  from  those  under  which  it  passed  before 
the  minds  of  Cuvier  and  the  Academicians  of  1830.  If  the 
alternative—  species  by  miracle  or  by  law — be  applied  to  palaBo- 
therium,  paloplotherium,  hipparion,  equus,  I  accept  the  latter 
without  misgiving,  and  recognise  such  law  as  continuously  opera- 
tive throughout  tertiary  time.'  By  law  (natural  law  or  secondary 
cause),  however,  we  understand  nothing  but  a  regular  and  re- 
curring phenomenon  where  the  acting  cause  is  not  touched  upon. 
This,  according  to  Owen,  is  the  Will  of  the  Creator  ;  for  he  adds  : 
'  I  believe  the  horse  to  have  been  predestined  and  prepared  for  man.' 
Hence  natural  law  is  in  this  case  not  opposed  to  miracle,  but  denotes 
merely  the  manifestation  of  an  Almighty  Will  working  towards 
a  definite  purpose.  The  same  view  is  expressed  also  by  Gaudry 
in  his  Considerations  sur  les  Mammiftres  (Paris,  1877),  where 
he  says:  'A  mesure  que  j'ai  cherch6  a  comprendre  1'histoire 
des  e"tres  fossiles,  il  m'a  paru  de  plus  en  plus  probable  que 
1'Auteur  du  monde  n'a  pas  cr66  iso!6ment  les  especes  succes- 
sives  des  ages  geologiques,  mais  qu'il  les  a  tire'es  les  unes  des 
autres.' 


PALAEONTOLOGY  SINCE  CUVIER.  49 

had  Cuvier  been  able  to  make  use  of  our  present 
material  his  conclusions  would  have  been  entirely 
different.  I  have  no  doubt  also,  that  our  great 
German  teacher  and  master,  Johannes  Miiller, 
would  likewise  have  set  aside  his  mystic  ideas  of 
the  origin  of  animals  and  of  creation,  in  view  of 
the  rising  sun  of  Darwinism. 

We  have,  of  course,  no  intention  here  of  giving 
an  account  of  the  gradual  extension  of  palaeonto- 
iogical  science  itself.  Our  object  is  rather  to 
explain  how  palaeontology  and  zoology  inter-pene- 
trate and  correlate  with  each  other.  And  it  is 
self-evident  that  in  doing  this  the  newer  period 
stands  prominently  forward,  since  the  revival  of 
the  theory  of  transformations.  One  of  the  condi- 
tions of  this  theory  of  development  is  the  overthrow 
of  Cuvier's  theory  of  catastrophes,  and  indeed  it 
was  finally  overthrown  for  all  time  to  come  when 
Lyell,  in  1832,  published  his  famous  '  Principles 
of  Geology.'  Lyell  there  proved  that  the  earth's 
crust  does  not  condense  and  change  suddenly,  and 
that  the  geological  periods  of  peaceful  life  have 
not  been  separated  from  each  other  by  general 
convulsions  extending  over  whole  continents,  but 
that  the  continuity  of  lands  and  seas  has  never 
been  entirely  interrupted,  even  though  they  have 


50  THE  MAMMALIA. 

often   been   disturbed  by  mighty  upheavings  and 
sinkings. 

The  connection  of  the  oceans  must,  in  fact, 
never  be  altered  to  account  for  the  migration  and 
distribution  of  the  animals.  For  instance,  it  is 
now  an  established  fact — from  deep-sea  investiga- 
tions— that,  since  the  chalk  period  at  least  the 
bottom  of  the  sea  has  experienced  only  unimportant 
changes,  changes  that  are  almost  imperceptible  in 
their  slowness  and  their  effect  upon  the  animal 
world ;  its  petrography  has,  in  fact,  undergone  such 
small  changes  that  it  may  be  said  that  we  are  still 
in  the  chalk  period,  and  that  the  formation  of 
chalk  is  still  proceeding.  And  further,  we  may 
assume  the  process  to  have  been  the  same  with  all 
the  other  and  earlier  geological  periods.  This 
theory  may,  moreover,  with  certain  limitations, 
be  applied  to  the  main  land.  Larger  accumula- 
tions of  land  of  some  consistency  are  probably  first 
perceived  in  the  Coal  formation,  and  there  can  be 
no  question  of  continents,  in  our  present  sense  of 
the  word,  till  the  Jura  and  Chalk  periods.  At  all 
events,  however,  temporary  connections  of  large 
Jura  islands— probably  also  the  accumulations  of 
land  belonging  to  the  Trias — must  have  also  existed. 
For,  not  merely  have  we  to  date  the  individual 


PALEONTOLOGY  SINCE   CUVIER.  51 

origin  of  the  Mammalia  as  far  back  as  the  Trias  at 
least,  and  probably  even  further  back,  but  we  have 
to  assume  that  the  class  was  one  of  pretty  consider- 
able extent.  And,  with  the  beginning  of  the 
Tertiary  period  we  already  stand  on  the  threshold 
of  the  present.  Whether  or  not  there  was  ever  a 
Sahara  ocean,1  or  Europe  ever  half  under  water  or 
encrusted  with  ice,  or  England  torn  away  from 
the  mainland  by  an  inroad  of  the  sea,  or  again 
whether  or  not  North  Africa  could  exchange  land 
animals  with  South  Europe  by  means  of  two 
isthmuses — these  and  other  incidents  on  a  grand 
scale  would  in  no  way  affect  the  truth  of  an 
uninterrupted  development.  There  remain,  it  is 
true,  a  series  of  animo-geographical  problems  un- 
solved, problems  which  are  geological  as  well ;  for 
instance,  the  case  of  Madagascar,  the  distribution 
of  wingless  birds,  the  Edentata,  the  isolated  cases 
of  the  Australian  fauna,  &c.  These  difficulties 
must  simply  be  accepted  as  such.  They  do  not 
hinder  our  recognising  the  natural  connection  of 
the  living  world  which  is  forced  upon  us  by  other 
facts,  and  they  do  not  oppose  our  present  concep- 
tion of  the  universe,  which  is  already  a  very  old 

1  This  conjecture  may  be  said  to  be  altogether  refuted  by  the 
latest  investigations. 


52  THE  MAMMALIA. 

one,  although  in  its  modern  form  it  has  the  new 
name  of  monism. 

However,  our  intention  was  to  speak  of  some  of 
the  work  that  had  been  accomplished  in  our  day  in 
the  domain  of  palaeontology,  which  is  intimately 
connected  with  that  of  zoology.  In  the  first  place, 
then,  we  must  mention  Kutimeyer's  works,  and 
can,  in  fact,  mention  only  some  of  his  most  eminent 
and  comprehensive  publications.  When  Darwin's 
grand  work  on  the  origin  of  species,  the  derivation 
of  domestic  animals,  and  the  influence  of  domes- 
tication on  the  transformation  of  the  original 
species  first  appeared,  and  was  being  universally 
talked  about,  as  much  interest  was  simultaneously 
aroused  by  the  discoveries  of  the  Swiss  lake-dwell- 
ings. They  gave  the  greatest  impetus  to  the  study 
of  modern  anthropology,  and  also  called  forth 
Eiitimeyer's  work  on  the  fauna  of  the  lake-dwell- 
ings,1 a  masterly  performance,  and  one  precisely 
such  as  was  required  by  the  new  theory  with  its 
very  imperfect  evidence.  The  manner  in  which  he 
explains  the  prehistoric  discoveries  by  the  races  of  the 
present  day  in  connection  with  the  diluvial  forms, 
pointing  out  certain  primary  forms  as  the  ancestors 

1  Kutimeyer,  Die  Fauna  der  Pfahlbauten  in  der  Schweiz. 
Basel,  1861. 


PALAEONTOLOGY  SINCE  CUVIEE.  53 

of  our  domestic  animals,  more  especially  of  the 
oxen,  the  accurateness  of  his  account  of  the  actual 
facts,  the  subtlety  and  carefulness  of  his  combina- 
tions— everything,  in  fact,  makes  Kiitimeyer's 
work  appear  as  if  it  had  been  ordered  for  a  given 
purpose.  Soon  after  this,  in  1863,  he  published 
a  work  on  fossil  horses.1  This  work,  which  was 
undertaken  by  way  of  explaining  the  relation  of 
the  genus  Horse  to  its  primeval  ancestors,  is,  in 
reality,  a  treatise  on  comparative  odontography,  or 
the  study  of  the  teeth  of  the  whole  class  of  hoofed- 
animals.  The  precision  with  which  he  points  out 
the  significance  of  the  characters  of  the  teeth,  the 
relation  of  the  milk  teeth  to  the  permanent  teeth, 
the  transitions  in  the  geological  successions  of  the 
genera  and  species,  and  traces  them  back  to  uni- 
versal principles  and  laws,  can  be  compared  only 
to  the  sagacity  of  a  Cuvier.  I  must  confess 
that  I  have  never  felt  my  interest  so  thoroughly 
aroused  in  a  subject,  wholly  distinct  from  my 
own  special  study,  as  it  has  been  by  these  two 
works  of  the  Basle  zoologist. 

Unfortunately,  our  greatest  authority  on  do- 
mesticated animals,  Herman  von  Nathusius,  who 
died  a  few  years  since,  and  was  always  vehemently 

1  Beitrtige  zur  Kenntniss  der  fossilen  Pferde 


54  THE  MAMMALIA. 

opposed  to  the  doctrine  of  descent,  has  left  us  a 
fuller  report  only  of  the  Pig  family  as  regards  what 
he  had  to  say  in  opposition  to  Kiitimeyer.  He 
never  published  a  full  account  of  his  valuable  com- 
parative investigations  respecting  the  domestic  ox. 
But  Eiitimeyer  has  published  a  later  and  admirable 
paper  on  this  very  subject,  his  object  being  to  show 
the  connection  between  the  living  oxen  and  all 
those  belonging  to  the  Diluvial  and  Tertiary  periods.1 
We  shall  presently  have  to  quote  from  Kiitimeyer, 
and  may  here  supplement  our  remarks  on  his  works 
by  mentioning  his  treatise  on  the  genus  Deer,2  which 
is  carried  out  in  the  same  spirit.  All  of  these  con- 
tributions are  masterpieces  as  regards  method,  for 
although  starting  from  a  limited  horizon,  they 
extend  over  the  whole  earth,  according  to  space 
and  time,  and  the  claims  of  a  practical  speculation 
are  set  forward  in  opposition  to  a  system  of  phi- 
losophy, according  to  which  our  investigations  in 
natural  science  would  not  have  advanced  beyond 
the  scheme  of  Plato's  Ideas  and  Aristotle's  Ente- 
lechise. 

Kiitimeyer's  investigations    are    not    confined 

1  Kiitimeyer,   'Versuch    einer  natiirlichen    Geschichte    des 
Rindes '  in  the  Reports  of  the  Swiss  PalcBontological  Society, 
xxii.  1877. 

2  Die  naturliche  Oeschichte  der  Hirsche  I.e.  1880. 


PALEONTOLOGY  SINCE  CUVIER.  55 

merely  to  the  objects  found  in  the  lake-dwellings, 
the  pea-ore  and  molasse  strata  of  his  native  country, 
for  in  his  monographs,  referred  to  above,  he  gene- 
rally makes  use  of  all  the  available  material  in  the 
European  collections.1  We  would  mention  together 
with  Kiitimeyer  two  French  naturalists,  Albert 
Gaudry  and  Filhol,  both  of  whom  have,  as  it  were, 
been  forced  by  their  important  discoveries  to  come 
forward  with  imposing  proofs  for  the  theory  of 
descent.  It  is  more  than  twenty  years  since  the 
publication  of  Gaudry 's  work  on  the  fossils  of 
Pikermi.2  Pikermi  is  the  name  of  a  hamlet  on  the 
road  between  Athens  and  Marathon,  near  which, 
in  the  deposits  of  a  mountain  stream  which  at  one 
time  rushed  along  there,  are  found  an  incredible 
accumulation  of  vertebrates,  more  especially  of 
mammals  belonging  to  the  upper  Tertiary  period. 
In  summing  up  the  results  of  his  investigations 
Gaudry  gives  his  readers  a  picture  of  a  tertiary 
landscape  and  its  forms  of  life,  which  we  cannot 
resist  quoting  word  for  word,  as  an  example  of  how 
our  imagination  should,  in  all  cases,  weave  single 

1  We  must  also  mention  here  his  extremely  instructive  paper 
on  Die  Herkunft  unserer  Thierwelt  (1867),  although  for  us  nowa- 
days it  certainly  presents  considerable  gaps. 

2  Animaux  fossi les  et  gfologie  de  VAttique  (1862). 


56  THE   MAMMALIA. 

dry  observations  into  a  picture  full  of  colour  and 
life. 

'  The  province  of  Attica  has  undergone  great 
changes  since  the  far  off  times  when  these  animals 
existed,  the  remains  of  which  are  accumulated 
round  about  Pikermi.  At  the  present  day  it  is 
a  strip  of  hilly  country  twenty  miles  (lieues)  long 
and  ten  broad.  That  this  locality  should  have 
been  considered  the  abode  of  the  gods,  and  should 
have  witnessed  the  glory  of  the  most  eminent 
minds  of  antiquity,  is  quite  intelligible.  But  the 
numerous  and  gigantic  four-footed  creatures  of 
primeval  times  required  a  wider  area,  and  they  are, 
moreover,  too  like  the  present  species  from  the 
interior  of  Africa  for  it  to  be  possible  that  they 
could  have  lived  in  Greece  under  the  same  con- 
ditions as  exist  at  present.  Without  doubt  at  one 
time  Europe  was  connected  with  Asia  by  un- 
interrupted plains  that  are  now  covered  by  sea. 
We  must  also  imagine  these  plains  to  have  been 
provided  with  a  more  luxurious  vegetation.  The 
marble  hills  of  Pentelicus,  Hymettus,  and  Lau- 
riurn  produce  now  only  small  plants  upon  which 
the  bees  find  their  food.  At  one  time  valleys  with 
a  rich  vegetation  must  have  run  along  by  the 
side  of  those  barren  hills,  and  grassy  meadows 


PALEONTOLOGY  SINCE   CUVJEK.  57 

alternated  with  splendid  forests.  For  an  abundance 
of  animal  life  demands  a  corresponding  fulness  of 
vegetation. 

*  Those  landscapes  were  enlivened  by  the  most 
varied  forms  of  mammals,  by  the  two-horned 
rhinoceros  and  the  gigantic  boar ;  also  by  monkeys 
leaping  from  rock  to  rock;  carnivora — from  the 
families  of  the  civet-cats,  martens  and  cats — all  on 
the  hunt  for  prey  ;  the  caves  of  the  Pentelicon  hills 
were  inhabited  by  hyaenas.  In  the  same  way  as 
quaggas  and  zebras  now  inhabit  Africa  in  enormous 
numbers,  immense  herds  of  Hipparion  must  have 
there  careered  across  the  plains.  Not  less  fleet  in 
their  movements,  and  of  an  even  lighter  build,  were 
the  antelopes,  also  in  great  numbers.  Every  troup 
of  a  distinct  species  would  be  distinguished  by  the 
form  of  their  horns  :  those  of  the  Palaeoreas  had  a 
spiral  twist  like  those  of  the  eland  of  the  Cape ;  the 
horns  of  the  Antidorcas  were  curved  in  the  form  of 
a  lyre ;  in  the  Palaeoryx  they  were  long  and  bent. 
The  horns  of  the  antelopes  resembled  those  of  the 
gazelles,  those  of  the  Tragoceras  were  placed  like 
those  of  goats.  Palaeotragus  was  distinguished  by 
a  slighter  build  and  a  narrower  skull,  with  horns 
situated  immediately  above  the  eyes.  But  Hella- 

dotherium  and  another  species  somewhat  akin  to 

7 


58  THE  MAMMALIA. 

the  giraffe  towered  above  all  of  the  Euminants. 
And  Ancylotherium  also — one  of  the  Edentata — 
was  a  creature  of  considerable  size  with  bent  toes. 
The  most  gigantic  of  all  the  animals,  however,  was 
the  Dinotherium.  What  a  magnificent  sight  it 
must  have  been  to  see  it  marching  about,  accom- 
panied by  two  species  of  mastodon !  In  those 
plains  was  heard  the  roaring  of  the  frightful 
Machairodus  with  its  sabre-shaped  canine  teeth ; 
and  many  other  species  associated  with  those 
named  above.  Their  cries  were  intermingled  with 
the  songs  of  birds,  and  in  the  concert  raised  by 
all  these  creatures  the  voice  of  man  alone  was 
wanting. 

*  Nowhere  does  the  earth  now  present  a  similar 
scene,  as  we  may  be  convinced  by  a  glance  at  our 
present  fauna.  In  the  virgin  primeval  forests  of 
America,  where  plant  life  is  met  with  in  the  full 
majesty  of  development,  we  might  expect  to  find  an 
equally  full  development  of  animal  life.  But  the 
four-footed  animals  are  less  powerfully  developed 
there  than  in  the  Old  World,  and  are  even  less  so  in 
Australia.  In  Europe  and  Central  Asia  they  have 
decreased  in  numbers  by  having  been  hemmed  in 
between  the  civilisation  of  the  temperate  zones  and 
the  ice  of  the  north.  The  largest  mammals  of  the 


PALAEONTOLOGY  SINCE   CUVIER.  59 

present  day  are  found  in  India  and  more  particularly 
in  Africa.  Delegorgue,  in  his  account  of  his  explora- 
tions in  Africa,  describes  a  lake  which  was  inhabited 
by  a  hundred  hippopotamuses,  and  within  a  space  of 
3,000  (?)  he  found  more  than  six  hundred  elephants. 
On  one  occasion  he  met  with  from  three  to  four 
hundred  hyasna-dogs,  and  again  with  troups  of  from 
four  to  five  hundred  quaggas.  Livingstone  relates 
that  he  frequently  saw  herds  of  more  than  four 
thousand  antelopes  passing.  One  of  his  descriptions 
of  this  wild  part  of  the  earth  runs  somewhat  thus : 
"  hundreds  of  zebras  and  buffaloes  were  seen 
crossing  the  plains;  numbers  of  elephants  were 
seen  feeding,  and  their  trunks  alone  showed  any 
signs  of  movement.  I  should  have  liked  to  have 
photographed  the  picture,  for  scenes  like  this  will 
vanish  when  firearms  are  brought  into  use,  and 
will  then  be  forgotten.  It  is  perfectly  marvellous 
what  immense  numbers  of  animals  are  to  be  seen 
crossing  the  country.  I  could  fancy  myself  trans- 
ported back  to  the  days  when  the  giant  sloth 
roamed  about  the  primeval  forests."  ' 

Gaudry  goes  on  to  say :  '  However  splendid 
such  pictures  may  be,  old  Greece  could  offer  even 
grander  scenes.  In  fact,  while  the  whole  of  Africa 
is  the  home  of  but  one  species  of  elephant,  Pikermi 


60  THE  MAMMALIA. 

had  two  different  forms  of  Mastodon  and  the 
Dinotherium,  the  principal  giants  among  the 
four-footed  animals.  Africa  has  only  one  kind  of 
giraffe.  Attica  possessed  a  giraffe  surpassing  all 
the  living  antelopes  in  size,  and  the  Helladothe- 
rium,  an  animal  with  short  legs,  it  is  true,  but 
larger  than  the  giraffes  in  bulk.  Among  the  living 
Kuminants  there  are  none  that  can  be  compared 
with  the  Helladotherium ;  the  camel  is  much 
inferior  in  size.  Africa  has  but  one  species  of 
rhinoceros,  distinguished  by  its  rudimentary 
incisors,  whereas  in  Pikermi  are  found  a  rhino- 
ceros of  the  African  type,  another  of  the  Asiatic 
species,  and  in  the  Acerotherium,  probably  also  a 
genus  related  to  the  rhinoceros.  The  huge  thick- 
skinned  animal,  the  Chalicotherium,  which  is  said 
to  have  been  discovered  in  Greece,  is  unequalled 
by  any  in  our  day.  The  skull  of  the  Eryman- 
thian  boar  exceeds  that  of  the  wild  boar  by 
one  third ;  and  among  the  latter  are  some  larger 
than  the  wart-hog  and  the  masked  boar  of  South 
Africa.  The  earth-hog  (Orycteropus),  the  largest 
of  the  Edentata  in  the  Old  World,  is  a  miserable 
creature  compared  with  the  Ancylotherium  of 
Attica.  Lastly,  the  lion  is  surpassed  by  one  of  the 
Carnivora  of  Attica,  the  panther  by  another. 


PALAEONTOLOGY  SINCE  CUV1ER.  61 

'  It  is  unjustifiable  to  dispute  the  existence  in 
the  Greece  of  that  period,  of  aquatic  animals — such 
as  the  river-horse,  sea-cow,  crocodile,  which  are  of 
frequent  occurrence  in  Africa — simply  because  their 
remains  have  not  yet  been  discovered  there.  For 
the  stratum  of  Pikermi  is  essentially  the  result  of  a 
mere  landslip,  inasmuch  as  the  layer  of  mud  which 
surrounded  the  bones  was  washed  down  from  the 
heights,  where  there  could  be  no  waters  inhabited 
by  those  gigantic  animals.  As  little  does  the 
absence  of  anthropomorphous  apes  prove  that  they 
never  existed  among  the  fauna  of  Southern  Europe ; 
the  gorilla,  for  instance,  inhabits  silent  forests 
where  scarcely  any  other  four-footed  animals  are 
met  with. 

'  In  Attica,  therefore,  more  species  of  large 
mammals  are  met  with  than  in  any  other  part  of 
the  present  world.  I  have  no  means  of  determin- 
ing the  number  of  the  individuals  of  the  different 
species,  but  there  is  no  reason  to  suppose  that 
this  number  was  smaller  than  those  of  the  present 
species.  Notwithstanding  the  great  number  of 
animals  observed  in  different  parts  of  Africa,  no- 
where could  a  greater  quantity  of  individuals  be 
found,  on  a  space  of  the  same  size,  as  where  I  made 
my  excavations.  This  space — only  a  small  portion 


62  THE  MAMMALIA. 

of  the  entire  stratum  containing  the  bones— was 
300  paces  in  length  and  sixty  in  breadth.  The 
quantity  of  bones  all  mixed  up  together,  which  a 
fortunate  excavation  at  times  brought  to  light, 
presented  a  remarkable  sight.  When  I  remind 
my  readers  of  the  fact  that  I  brought  back  with 
me  1,900  pieces  of  Hipparion,  more  than  700 
pieces  of  Bhinoceros,  500  of  Tragoceras,  &c.,  it 
will  readily  be  understood  that  I  was  obliged  to 
leave  behind  me  on  my  last  journey  the  remains  of 
the  commoner  species  of  animals,  to  collect  which 
would  only  have  delayed  my  examination  of  the 
rarer  pieces.' 

Gaudry  was  able  in  every  direction  to  deter- 
mine the  position  of  the  different  species  which 
had  lived  together  on  the  ancient  ground  of 
Pikermi,  midway  between  the  Miocene  and  Pliocene 
deposits.  One  main  result  of  his  comparisons  was 
the  proof  that  almost  all  belonged  to  that  sort  of 
intermediate  form  of  which  Cuvier  had  so  greatly 
felt  the  want.  '  If,'  says  Gaudry,  '  with  all  the 
eminent  palaeontologists  of  to-day,  we  add  all  the 
other  known  fossils  and  living  species  to  those 
found  at  Pikermi,  we  feel  convinced  that  the  gaps 
would  disappear  in  the  same  proportion  as  new  dis- 
coveries are  made.'  Thus  he  found  himself  obliged 


PALEONTOLOGY  SINCE   CUVIER.  63 

to  set  up  pedigrees — those  systems  of  the  probable 
geological  connection — which  are  ridiculed  only  by 
persons  who  lack  the  preliminary  knowledge  for 
forming  a  judgment. 

Yet  Gaudry,  like  other  of  his  countrymen  who 
maintain  the  incontestability  of  the  theory  of 
descent,  is  not  a  disciple  of  Darwinism — i.e.  of 
finding  a  proof  for  the  theory  of  descent  in  the 
hypothesis  of  natural  selection  in  the  struggle  for 
existence.  He,  like  K.  Owen,  remains  within  the 
realm  of  miracles,  and  supposes  a  personal  Creator 
to  have  directed  the  countless  forms  of  develop- 
ment towards  definite  and  pre-ordained  purposes. 
With  this  conception  of  things — which  at  a  certain 
point  sets  sober  inquiry  aside — the  assumption  of 
accident  has  to  be  met,  and  accident,  in  the 
opinion  of  Darwin's  opponents,  is  raised  to  the 
rank  of  principle.  We  do  not,  of  course,  intend 
here  to  enter  into  any  further  polemics  while 
speaking  of  the  great  achievements  of  a  man  who 
admits  his  belief  in  such  things,  but  still  we  must 
again  remark  that  even  that  which  is  called 
accident  is  not  beyond  the  pale  of  legitimate  occur- 
rence. We  leave  it  to  the  reader  to  decide  whether 
it  appears  more  reasonable  to  assume  that  the 
absolute  intelligence  of  a  personal  Creator  should 


64  THE  MAMMALIA. 

break  off,  for  no  result,  millions  of  commenced 
series,  than  that  so-called  accident  should  prevail 
within  the  absolute  laws  of  Nature. 

Gaudry,  in  a  very  admirable  work,1,  has  given 
an  account  of  the  main  substance  and  the  results 
of  all  the  palaeontologico-zoological  inquiries. 

Of  even  greater  importance  to  the  question 
of  transition-  and  intermediate  forms  are  the 
works  of  Filhol,  a  young  compatriot  of  Gaudry's. 
We  refer  to  his  papers  on  the  '  Phosphorites  of 
Quercy,' 2  which  appeared  in  1876  and  1877 ;  also 
his  article  on  the  '  Fossil  Mammals  of  St.  Gerard  le 
Puy,'  and  his  comprehensive  treatise  on  the  *  Fossil 
Mammals  of  Ronzon,'  which  appeared  in  1882. 

Phosphorite  belongs  to  the  Upper  Eocene  for- 
mation of  South-western  France,  deposits  of  non- 
crystallised  phosphated  lime.  It  is  found  in  cracks 
and  hollows  which  have  been  filled  up  from  above. 
The  deposit,  Filhol  says,  was  no  doubt  the  result 
of  warm  springs,  which  from  time  to  time  caused 
extensive  inundations,  and  drowned  or  suffocated 


1  Gaudry,    Les  enchainements  du  monde  animal  dans  les 
temps  geologiques.    Mammiferes  tertiaires  (1878). 

2  Filhol,  Becherches  sur  les  Phosphorites  du  Quercy.    Etudes 
sur  les  fossiles  qu'on  a  rencontre's,  et  specialement  les  mammiferes. 
Annales  des  sciences  geologiques,  vii.,  viii. ;  Mammiferes  fossiles  de 
St.-Oerard  le  Puy,  Ibid.  x. ;  Mammiferes  de  Ronzon,  xii. 


PALAEONTOLOGY  SINCE  CUVIER.  65 

all  living  things.  Pachyderms,  Euminants,  Bo- 
dents,  Carnivora,  all  met  with  a  rapid  death  to- 
gether; frequently  the  animals  were  buried  while 
their  skeletons  were  still  intact.  The  deposits  at 
Quercy  have  furnished  the  most  important  facts 
that  have  yet  been  discovered  for  the  study  of 
the  fossil  Mammalia  in  Europe.  They  are  as  im- 
portant as  the  more  recent  discoveries  in  America. 
The  characteristics  of  the  animals  met  with  in 
France  are  perhaps  less  remarkable  and  conclusive ; 
they  are  not  striking  at  first  sight,  and  it  is  only  by 
a  very  careful  study  of  them  that  we  perceive  their 
true  value.  The  transitions  are  extremely  delicate  ; 
we  have  there  to  do  with  shades  of  difference,  not 
with  differences  clearly  expressed.  Hence  the 
period  of  Phosphorite  witnessed  great  changes,  and 
the  types  now  existing  were  giving  signs  of  appear- 
ing. The  influence  of  natural  circumstances,  which 
we  are  not  able  to  define  more  narrowly,  but  the 
traces  of  which  have  been  discovered,  changed  the 
species  in  various  ways  and  gave  rise  to  varieties 
which  became  fixed,  and  thus  passed  over  into  a 
new  species.  Thus  far  Filhol. 

Of  the  incredible  wealth  of  forms  among  the 
higher  classes  of  animals  in  the  South-western 
Europe  of  those  days,  we  have  proofs  in  the  fact 


66  THE  MAMMALIA. 

that  Filhol  distinguishes,  among  the  beasts  of  prey 
alone,  some  forty-two  species.  In  this  abundance 
of  forms,  in  the  occurrence  of  these  most  varied 
kinds  of  flesh-  and  plant-eaters — which  cannot  be 
imagined  without  a  struggle  for  existence — we  can, 
as  it  were,  quietly  watch  the  gradual,  very  gradual, 
process  of  transformation,  the  origin  of  species.  The 
inestimable  value  of  Filhol's  researches,  like  those 
of  Gaudry,  is  that  they  could  extend  over  thousands 
of  objects.  His  investigations  are  peculiarly  valu- 
able, owing  to  the  fact  that  three  of  the  most  im- 
portant deposits  of  France  and  of  Europe  (Quercy, 
Eonzon,  and  Gerard  le  Puy — the  rich  outcome  of 
which  he  was  able  to  work  upon),  belong  to  three 
closely  connected  geological  horizons.  And  Filhol 
has  compared — in  a  way  that  scarcely  any  other 
palaeontologist  has  done — the  changes  and  advances 
of  the  animal  world  from  one  of  these  periods  to 
the  other,  in  their  specialisations,  and  has  placed 
these  in  the  foreground  as  the  general  result  of  his 
most  careful  and  detailed  accounts. 

Another  investigator  of  great  enterprise,  Wol- 
demar  Kowalewsky,1   has    unfortunately   died  at 


1  W.  Kowalewsky,  Sur  V Anchitherium  Aurelianense  Cuv. 
(Acad.  de  St.  Petersbourg,  1873)  :  Osteology  of  the  Hyopotamidce 
(Philoso.  Transact.  1873) ;  Versuch  einer  natttrlichen  Classified- 


PALAEONTOLOGY  SINCE  CUVIER.  67 

too  early  an  age.  His  works  also  belong  to  the 
seventh  decade  and  treat  more  especially  of  the 
Hoofed  animals ;  they  contain  the  most  important 
supplements  to  Kiitimeyer's  works,  for  he,  at 
times,  takes  up  entirely  new  standpoints  for  deter- 
mining the  connection  between  the  present  and 
the  remote  periods.  He  has  not  done  so  much  in 
bringing  to  light  new  forms,  as  in  carefully  com- 
paring those  long  since  known.  Certain  opinions 
about  primary  and  fundamental  forms,  such  as 
Palaeotherium,  Anoplotherium,  Dichobune,  and 
others,  which  had  become  traditional  since  Cuvier's 
day,  he  has  finally  corrected,  and  has  in  a  masterly 
way  clearly  defined  the  essential  differences  be- 
tween odd-hoofed  and  pair-hoofed  animals ;  he  has 
also  endeavoured  to  explain  the  disappearances  of 
forms,  and  the  continuance  and  transformation  of 
others  by  very  careful  examinations,  more  particu- 
larly of  the  hand  and  foot.  Accordingly  he  has 
set  up  pedigrees  which  do  not  indeed  differ  in 
many  points  from  the  results  given  by  Kiitimeyer, 
but  they  are  certainly  proofs  of  the  extremely  sug- 
gestive and  ingenious  manner  in  which  he  con- 
templates the  primeval  world,  in  its  continuity  with 

tion  der  fossilen  Hufthiere.  Monographic  der  Gattung  Anlhra- 
cotherium  (Palseontographica,  1876). 


68  THE  MAMMALIA. 

the  earth  as  it  is  nowadays.  Specially  ingenious 
I  consider  his  distinction  between  the  adaptive 
and  inadaptive  reduction  of  the  limbs,  which  we 
shall  have  to  consider  more  in  detail  when  discuss- 
ing this  point. 

Having  now  pointed  out  the  direction  in  which 
these  investigators  have  worked,  and  their  con- 
ception of  things  in  general  as  distinguished  from 
those  of  their  numerous  fellow-workers  in  the 
domain  of  the  higher  animals,  and  having  further 
referred  to  the  stimulus  which  their  studies  have 
given  to  the  theory  of  descent,  I  may  now  confine 
myself  to  mentioning  them  only  in  so  far  as  they 
concern  the  palaeontology  of  the  Old  World. 

Within  the  last  fifteen  years  a  series  of  sur- 
prising discoveries  have  been  made  concerning  the 
paleontology  of  America ;  these  discoveries  have 
almost  subverted,  at  all  events  completely  modified, 
the  opinions  that  had  hitherto  prevailed  as  to  the 
distribution  and  derivation  of  animals,  in  so  far  as 
they  concern  the  exchange  and  succession  between 
the  Old  and  New  World.  We  have  a  summary  of 
the  zoo-geographical  inquiries  into  those  primary 
periods  in  a  work  of  Eiitimeyer's,1  not  very  com- 
prehensive but  rich  in  substance.  He  there  says : 

1  Ueber  die  Herkunft  unserer  Thierwelt,  18G3. 


PALEONTOLOGY  SINCE  CUVIER.  69 

'  The  whole  surface  of  the  earth  of  the  Old  World 
during  the  Tertiary,  as  far  as  is  known,  formed  one 
single  natural  domain  for  the  mammal  fauna ;  it 
was  more  extensive,  but  the  same  as  that  which  had 
previously  sustained  the  animal  world  of  the  Eocene 
formation.'  From  here  the  primeval  Mammalia 
proceeded  not  only  southward  into  Africa,  but  had 
also,  as  it  seems,  found  their  way  into  the  New  World 
by  an  isthmus  of  land  connecting  Europe  with 
North  America ;  partly  also — as  is  shown  by  the 
fossil  elephants  of  Japan — from  Northern  Asia  in 
the  direction  of  the  Aleutian  Islands.  The  fauna  of 
North  America,  the  principal  portion  of  which,  to 
all  appearances,  was  not  indigenous  to  the  country, 
then  wandered  southwards,  following  the  course  of 
the  principal  mountain  ranges,  where  they  met 
members  of  a  foreign  fauna  coming  northwards 
from  the  south,  and  which  in  the  more  recent 
periods  even  crossed  the  isthmus.  At  all  events, 
the  Mammalian  fauna  of  North  America  appeared 
as  inferior  and  dependent  upon  that  of  the  East, 
and  immigration  from  the  New  to  the  Old  World 
seems  a  doubtful  matter  and  even  a  question  of 
secondary  importance.  As  Eiitimeyer  goes  on  to 
say: '  The  Miocene  fauna  of  Nebraska  is  the  offspring 

of  the  Eocene  formation  of  the  Old  World.     The 

8 

JgS* 

OF   THE 

UNIVERSITY 


70  THE  MAMMALIA. 

Pliocene  fauna  of  Niobrara,  which  lie  buried  in  the 
same  ground  as  Nebraska,  but  in  a  later  stratum 
of  sandstone,  prove  this  in  an  even  greater  mea- 
sure. Elephants,  tapirs,  and  various  species  of 
horses  differ  scarcely  at  all  from  those  of  the  Old 
World:  the  boars,  to  judge  from  their  dentition, 
are  descendants  of  the  Palaeochoerus,  &c.,  of  the 
European  miocene  deposits.' 

Even  when  these  remarks  of  Butimeyer  were 
written,  we  possessed  an  eminent  work  on  the 
Tertiary  fauna  of  North  America  by  Leidy.1  But 
since  those  days  the  discoveries  made  have  been 
so  extraordinarily  numerous,  and  the  immense 
variety  of  animals  that  lived  there  has  proved  so 
much  more  varied  than  the  European  fauna,  that 
American  investigators,  headed  by  Cope  and 
Marsh,  have  come  to  the  conclusion  that  America 
was  not  colonised  with  Mammalia  from  the  Old 
World,  but  that  the  former  gave  Europe  some 
of  its  original  superfluity;  even  the  theory  ac- 
cepted by  Kiitimeyer,  that  the  Tertiary  strata 
of  America  were  in  part  somewhat  more  recent 
than  ours,  is  proved  to  have  been  the  reverse. 
Marsh  writes  in  1877 :  '  These  natural  divisions 
(of  the  American  Tertiary)  are  not  the  exact 

1  The  Ancient  Fauna  of  Nebraska,  1853. 


PALEONTOLOGY  SINCE  CUVIEE.  71 

equivalents  of  the  Eocene,  Miocene,  and  Pli- 
ocene of  Europe,  although  usually  so  considered 
and  known  by  the  same  names ;  but,  in  general, 
the  fauna  of  each  appears  to  be  older  than  that  of 
its  corresponding  representative  in  the  other  hemi- 
sphere—  an  important  fact  not  hitherto  recognised.' 

The  area  of  the  life  which  extended  throughout 
the  Tertiary  period,  and  showed,  in  part,  a  closer 
connection  than  can  be  proved  in  the  case  of 
Europe,  lies  along  both  sides  of  the  Eocky  Moun- 
tains. To  the  west — more  especially  in  the  region 
of  the  Green  Eiver — it  extends  up  to  the  height 
of  the  Great  Salt  Lake.  It  is  more  extensive 
still  to  the  east,  where  the  so-called  Bad  Lands 
(Mauvaises  terres)  in  the  state  of  Dakota  are  the 
most  productive  centre. 

Leidy's  work  on  the  ancient  fauna  of  Nebraska, 
which  marks  an  epoch  in  the  palaeontology  of  the 
United  States,  has  been  completed  by  his  investi- 
gations on  the  extinct  vertebrates  of  the  Western 
Territories.1  Since  then  not  a  year  has  passed 
without  Cope,  and  Marsh  especially,  bringing  to 
light  new  branches  of  this  rich  tree  of  knowledge.2 

1  Leidy,  '  Contributions  to  the  Extinct  Vertebrate  Fauna  of 
the  Western   Territories,'    United  States  Geographical  Society. 
Washington,  1873. 

2  We  do  not  yet  possess  any  detailed  account  of  this  incom 


72  THE  MAMMALIA. 

No  less  magnificent  than  these  discoveries 
relating  to  the  Tertiary  mammals,  are  the  disclo- 
sures concerning  the  Diluvial  mammals  that  have 
been  made  since  Cuvier's  day.  But  it  is  chiefly 
South  America  that  attracts  our  attention  as 
regards  these.  Most  remarkable  of  all  are  the 
discoveries  of  fauna  from  the  Upper  Tertiary  and 
Diluvial,  which  were  found  mainly  in  the  caves 
of  the  Brazilian  province  of  Minas  Geraes,  and 
also  in  the  deposits  of  Argentinium  and  Bolivia. 
Fossil  remains  from  the  Eocene  are  very  rare,  and 
of  these  remains  those  of  the  Palseotherium  and 
Anoplotherium  from  Europe,  point  to  connections 
of  which  geology  has  as  yet  been  unable  to  give 
any  explanation.  Testimonies  from  the  Miocene 
are  altogether  wanting.  On  the  other  hand,  the 
later  deposits  show  an  extremely  peculiar  character, 
owing  to  numerous,  and  in  part  colossal  forms  of 

Edentata.     Whether  some  of  their  most  wonderful 

• 

representatives,   such    as    the    giant    sloth,   were 

parably  valuable  material.  We  have  to  refer  to  the  short  papers 
contributed  to  the  American  Naturalist,  Stillman's  Journal, 
also  to  the  Proceedings  of  the  Amer.  Philos.  Society.  Marsh 
gives  a  survey  in  the  paper  on  the  Introduction  and  Succession 
of  Vertebrate  Life  in  America,  1877  ;  also  Cope's  article,  '  Mam- 
malia Bunotheria,'  in  the  Report  upon  United  States  Geogra- 
phical Survey  West  of  the  One  Hundredth  Meridian,  vol.  iv. 
Palaeontology,  1877. 


PALEONTOLOGY  SINCE  CUViER.  73 

driven  northwards  when  the  isthmus  was  restored, 
or  whether,  according  to  Marsh,  the  north  was 
the  original  home  of  this  animal  likewise,  does 
not  seem  to  be  a  settled  point.  This  Megathe- 
rium was  already  known  to  Cuvier.  But  most  of 
the  .Edentata  were  not  discovered  till  later,  and 
Lund's  discoveries  l  in  the  cave-deposits  of  Brazil 
may  be  said  to  mark  an  epoch;  in  more  recent 
times,  Burmeister,2  a  veteran  in  zoological  research, 
has  in  a  masterly  way  described  the  gigantic 
Argentine  armadilloes  and  other  animals. 

A  comparison  of  our  present  fauna,  both  of 
Europe  and  Asia — as  well  as  of  the  two  Americas 
— with  that  of  the  Diluvial  period  in  these  same 
regions,  will  show  the  present  at  a  very  great 
disadvantage;  Wallace  might  well  say  that  we 
live  in  a  world  which  is  zoologically  very  im- 
poverished, and  from  which  the  hugest,  wildest, 
and  strangest  forms  have  now  disappeared.  ¥his 
disappearance  of  numerous  races  of  animals,  in  the 
eastern  and  western  hemispheres,  almost  makes 
the  impression  as  if  it  had  been  the  result  of  some 
such  catastrophe  as  we  have  declared  ourselves 

1  Lund,  Brasiliens  Dyrverden.    Copenhagen,  1841-45. 

2  Burmeister,  Annales  del  Museo  ptiblico  de  Buenos  Aires^ 
1864,  p.  9. 


74  THE  MAMMALIA. 

unable  to  admit.  At  all  events,  the  period  within 
which  the  European  mammoths  and  their  asso- 
ciates, the  American  mastodons,  the  giant  sloths 
and  giant  armadilloes,  rapidly  died  out,  must  have 
been  very  short  in  a  geological  sense  of  the  word. 
But  there  was  no  general  destruction  or  dying  out, 
only  a  portion  of  the  species  became  altogether 
extinct,  e.g.  the  horses  of  America :  one  portion 
found  means  of  differentiating,  to  adapt  themselves 
to  a  new  locality,  or  returned  at  a  later  period  to 
their  old  home  when  the  hindrances  to  their  ex- 
istence no  longer  prevailed.  Among  those  inhabit- 
ants of  the  earth  able  to  cope  with  the  existing 
difficulties  was  Man,  who  may,  with  positive 
certainty,  be  seen  struggling  through  the  whole 
Diluvial  period.  All  these  signs  of  life  succumbed, 
or  had  partially  to  withdraw,  before  the  great  ice 
formations  which  took  place  during  the  sub- 
divisions of  the  Diluvial  age.  The  cloak  of  ice — 
evidently  of  many  thousand  years'  duration — which 
still  persistently  envelops  Greenland,  while  Norway 
and  Sweden,  in  the  same  latitudes,  enjoy  the  most 
splendid  green  summers,  gives  us  a  vivid  picture 
as  to  how  we  have  to  conceive  the  enormous 
glacial  formations  in  Europe  and  America  during 
the  Diluvial  period. 


PALEONTOLOGY  SINCE  CUV1EE.  75 

An  extremely  interesting  question  in  palseon- 
tology,  and  one  which  is  at  present  engaging  the 
attention  of  geologists,  is,  whether  North  Germany 
was  under  water  or  encrusted  with  ice  during 
one  division  of  the  Diluvial.  Nehring ]  has  come 
forward  in  support  of  the  latter  hypothesis.  He 
.  adduces  weighty  arguments  against  the  drift  theory, 
i.e.  against  the  generally  accepted  supposition  that, 
during  one  subdivision  of  the  Diluvial,  North  Ger- 
many was  under  water,  and  that  the  Scandinavian 
blocks  of  granite  scattered  over  the  land  were 
deposited  by  icebergs  from  the  north.  His  chief 
argument  against  this  theory  is  the  utter  want  of 
any  remains  of  marine  animals,  the  want  of  every 
trace  of  shore  fauna.  Some  few  discoveries  in 
East  and  West  Prussia,  in  Holstein  and  about 
Hamburg,  which  have  been  examined  by  Berendt 
and  Jentzsch,  '  prove  only,'  says  Nehring,  '  that 
certain  limited  portions  of  North  Germany  were, 
during  the  ice  period,  covered  by  the  sea  perma- 
nently, or  perhaps  only  for  a  time.'  For,  he  adds, 
it  was  not  sea  but  glaciers  which  covered  the  low- 
lying  plains  of  Germany,  as  far  as  the  Hartz  and 
the  other  mountain  ranges  to  the  south.  Where 

1  Nehring,  '  Faunistische  Beweise  fur  die  ehemalige  Verglet- 
Bcherung  von  Norddeutschland,'  Kosmos,  vii.  1883. 


76  THE  MAMMALIA. 

the  glaciers  themselves  lay  there  are  absolutely 
no  remains  of  animals,  but  remains  are  found  in 
those  localities  where  the  edges  of  the  former 
glaciers  must  have  been  situated.  And  all  of  these 
remains  belong  to  an  Arctic  Alpine  fauna,  such  as 
now  live  round  about  the  North  Pole — the  reindeer, 
musk  ox,  arctic  hare,  lemming,  arctic  fox,  arctic 
hen,  arctic  owl.  The  occurrence  of  all  these  animals 
is  carefully  pointed  out  by  Nehring,  for  instance, 
at  Tiede  in  Brunswick,  and  at  Westeregeln.  The 
nature  of  the  bones,  and  the  discovery  of  young 
specimens  by  the  side  of  the  older  animals,  shows 
that  the  conclusion  must  be  that  the  animals  lived 
there.  It  is  still  uncertain  whether  there  was  only 
one,  or  two,  or  even  several  ice  periods.  The 
Glacial  period  with  its  fauna  was  followed  by  one 
with  an  improved  climate,  which,  however,  did  not 
as  yet  permit  the  growth  of  forests.  A  new  fauna 
appears  corresponding  with  that  of  the  steppes  of 
South-western  Siberia — jerboa,  suslik,  lagomys, 
saiga-antelopes.  Gaudry,  too,  has  shown  that  the 
latter  were  also  very  widely  distributed  in  France. 
If  Northern  Europe  had  only  one  Glacial  age,  then 
the  period  of  the  steppe  fauna  marks  the  retreat  of 
the  glaciers  in  the  very  different  configuration  of 
the  land.  If,  however,  there  were  two  Glacial 
periods — as  seems  very  probable  at  least  in  the  case 


STRATA  OF  THE  TERTIARY  FORMATION.        77 

of  Switzerland — then  those  periods  during  which 
the  steppe  fauna  might  have  dispersed  must  have 
been  the  intermediate  epochs.  However,  we  still 
require  much  enlightenment  on  this  point,  and  much 
also  remains  to  be  explained  as  regards  the  causes 
of  all  these  ice  formations. 

It  is  not  known  how  far  back  Man  extends  into 
the  Tertiary  period.  In  the  central  and  northern 
latitudes  of  the  Old  World  as  well  as  of  America 
he  could,  of  course,  not  gather  into  communities, 
or  rise  above  his  origin,  till  the  Glacial  period  (as 
may  be  assumed)  gave  way  to  incalculably  long  ages 
of  assured  order  in  the  later  geological  period. 
And  Man's  distribution  over  the  earth  is  accom- 
panied by  a  diminution  of  the  animals. 

THE  STRATA  OF  THE  TERTIARY  FORMATION. 

Air-breathing  animals  are  met  with  first  in  the 
Coal  formation.  Thereupon  we  have  in  succession 
the  Dyas  formation  (in  Germany,  Kupferschiefer 
and  Bothliegendes),  the  Trias  (bunter  Sandstein, 
Muschelkalk,  Keuper),  the  Jura  with  its  numerous 
divisions,  and  the  Chalk.  We  possess  a  few  fossil 
remains  of  Mammalia  even  from  the  Trias  and 
Jura  formations.  Nothing  is  preserved  in  the 
Chalk.  On  the  other  hand,  the  subdivisions  of  the 
Tertiary  are  unusually  rich  in  fossil  remains  of 


78  THE  MAMMALIA. 

mammals.  By  way  of  pointing  out  the  position 
and  succession  of  the  formations,  we  will  here  add 
a  tabular  view  of  the  more  important  strata  ;  first 
those  of  the  Old  World,  where  Central  Europe  is, 
of  course,  the  part  that  has  been  longest  and  best 
known,  and  then  a  comparison  of  the  divisions  of 
the  Tertiary  of  North  America.  At  the  same  time 
the  names  of  the  more  important  species  are  given 
by  the  side  of  the  different  strata  in  which  they  are 
found.  All  that  lies  above  the  Tertiary  formations 
is  considered  as  Diluvium,  the  lowest  strata  of 
which  are  frequently  also  called  Quartary  or  Quar- 
ternary.  It  need  scarcely  be  stated  that  there  is 
no  sharp  boundary  between  the  uppermost  Tertiary 
strata  and  the  lower  Diluvial,  and  that  the  separa- 
tion of  the  upper  Diluvial  from  the  later  Alluvium 
is  equally  indefinite.  Owing  to  this  difficulty 
in  distinguishing  the  different  formations,  most 
palaeontologists  prefer  speaking  merely  of  a  lower  or 
an  upper  stratum  of  the  Tertiary,  in  place  of  sub- 
dividing it  into  Lower,  Middle,  and  Upper  Tertiary, 
Miocene  or  Pliocene.  The  following  arrangement  is 
partly  taken  from  a  tabular  view  given  by  Gaudry ; l 
in  the  case  of  America  we  have  followed  Marsh. 

1  Gaudry,  Considerations  sur  Us  Mammifores  qui  ont  vtcu  en 
Europe  a  la  fin  de  Vtyoque  miocdne.    Paris,  1873. 


STKATA  OF  THE  TERTIARY  FORMATION.        79 


A.    TERTIABY  FORMATIONS  OF   THE   OLD 
WORLD. 

PLIOCENE. 
19.  Perrier.     Crag  of  Norwich.     Val  d'Arno. — Numerous  deer. 

Antelopes  rare.    Elephants,     l^aslodoa. 
18.  Marl  of  Montpellier.    Lignite  of  Casino.  —Both  deer  and 

antelopes.    Hyaenarctos. 

VIENNA  BASIN   II. 

UPPER  MIOCENE. 
17.  Pikermi.       Baltavar.        Mont-Leberon. —  Helladotherium. 

Ictitherium.     Hyaena. 
16.  Siwalik  Hills. 
15.  EppelsTieim.     Oeningen. — Hipparion.      Sus.     Dorcatherium. 

Tapir.     Dinotherium.     Simocyon. 

MIDDLE  MIOCENE. 

14.  Sansan.  Georgsmilnde  and  Gilnzberg.  Eibiswald.— Ante- 
lopes. Mastodon. 

VIENNA  BASIN  I. 

13.  Limestone  of  Montabuzard.  Sand  of  Orleans.  Lignite  of 
Monte-Bamboli. — Palseochoerus.  Cainotherium.  Dremo- 
therium.  Dicroceras.  Dinotherium.  Mastodon. 

LOWER  MIOCENE. 

12.  St.  Gtrard  le  Puy  (on  the  Allier). — Anchitherium.     Dremo- 

therium. 

11.  Sand  of  Fontainebleau.    Lignite  of  Cadicona. — Ehinoceros. 
10.  Lime  rocks  of  Ronzon. — Gelocus. 

UPPER  EOCENB. 
9.  Phosphorite  of  Quercy. 
8.  Lignite  of  Debruge. 
7.  Paris  Gypsum.    Hampshire. 
6.  Sands  of  Beaucliamp. 


80  THE  MAMMALIA. 

5.  Paris  Coarse  Limestone.—  Characteristic  are  entelodon,  hyse- 
nodon,  pterodon,  dichobune,  palseotherium,  anoplotherium, 
xiphodon.  In  the  upper  strata  are  found  also  among 
others  anthracotherium,  cainotherium. 

MIDDLE  EOCENE; 
4.  Maureniont.    Pea-ore.    Egerkingen. 

LOWER  EOCENE. 

3.  London  clay. — Hyracotherium.    Pliolophus. 
2.  Lignite  of  Soissonnais. — Coryphodon.    Palaeonictis. 
1.  Sandstone  of  La  Fere.—  Arctocyon. 


STRATA  OF  THE  TERTIARY  FORMATION.        81 


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82  THE  MAMMALIA. 


n. 

SPECIAL   COMPARISON  OF  THE  LIVING 
MAMMALIA  AND   THEIR  ANCESTORS. 

IN  entering  now  upon  an  examination  of  the 
different  groups  of  the  living  Mammalia  according 
to  their  historical  or  palaeontological  past — an  ex- 
planation of  that  which  has  come  to  be  out  of  that 
which  has  been — the  method  to  be  followed  is  self- 
evident  :  a  systematic  arrangement,  proceeding 
from  the  lowest  to  the  highest  forms,  comprising 
the  result  of  anatomical  as  well  as  of  palseonto- 
logical  considerations.  The  lower  groups  of  Mam- 
mals are,  of  course,  those  which  have  retained  the 
inherited  qualities  of  their  ancestors  most  distinctly, 
and  have  changed  least.  This  does  not  necessarily 
include  the  certainty  that  they  inhabited  the  earth 
at  an  earlier  period  than  all  those  whose  skeleton, 
brain,  and  fcetal  development  show  a  pre- existence 
of  the  lower  forms,  but  end  with  a  higher  result. 
The  lower  Mammals  may  have  remained  as  a  rem- 
nant of  a  group  whose  nearest  relatives — at  first, 


LIVING   MAMMALIA  AND  THEIK  ANCESTORS.      83 

by  scarcely  noticeable  deviations  —  raised  them- 
selves above  their  cousins  by  making  use  of  the 
advantageous  changes  and  adaptations  in  their 
organisations.  And  yet  the  probability  is  that  the 
lowest  animal  forms  were,  in  general,  also  the 
oldest  geologically. 

Although  even  Cuvier  had  prepared  the  down- 
fall of  Buffon's  indefinite  idea  of  arranging  the 
animal  kingdom  into  one  series,  still  it  was  not  till 
our  own  day  that  it  became  generally  admitted  that 
the  conception  of  a  figurative  expression  for  the 
system  could  only  take  the  form  of  an  immense 
tree,  with  hundreds  of  branches  and  thousands  of 
twigs.  The  animals  we  see  living  to-day  are  the 
tips  of  the  twigs  and  shoots ;  those  that  preceded 
them  must  be  looked  for  down  towards  the  branches, 
and  from  these  again  down  towards  the  trunk.  The 
comparison  of  a  tree,  however,  serves  only  as  a 
means  of  arrangement.  On  our  grand  tree  of  life, 
the  branchings  are  all  unlike  one  another,  and 
show  resemblances  only  where  they  are  in  close 
proximity ;  the  farther  they  have  branched  off  from 
the  tree  the  more  different  do  they  become. 

From  another  point  also  the  figure  of  a  tree 
will  give  us  a  distinct  idea  of  the  actual  state  of 
things.  The  farther  we  go  back  into  the  history 


84  THE  MAMMALIA. 

of  the  existing  animal  forms  the  nearer  we  come 
to  their  origin.  In  cases  where  to-day  no  connec- 
tions seem  to  exist  except  the  characteristics  of  the 
class  and  order,  in  going  back  we  find  more  definite 
and  ever  clearer  resemblances,  till  finally  the  com- 
mon original  forms  are  discovered.  These  have 
often  been  called  '  mixed  forms,'  which  term,  how- 
ever, does  not  properly  indicate  the  nature  of  the 
matter.  For  in  most  cases  the  question  is  much  less 
about  a  combination  of  marked  characteristics  which, 
in  earlier  times  were,  and  at  present  are  distributed 
over  different  branches,  than  about  a  still  undifferen- 
tiated  basis  that  has  in  various  directions  proved 
itself  transformable.  For  instance,  the  Hoofed 
Animals,  which  when  first  met  with  are  unfortu- 
nately already  very  marked  in  character,  possess 
the  full  number  of  toes  and  a  good  supply  of  teeth. 
Of  the  teeth  it  might  indeed  be  said  that  they  show 
a  'mixed  character,'  inasmuch  as  the  front  ones 
are  more  adapted  for  attack  and  defence,  while  the 
rest  are  specially  adapted  for  munching  vegetable 
substances.  But  if  the  earliest  forms  of  Hoofed 
Animals  and  the  earliest  forms  of  Carnivora  point 
to  animals  resembling  the  Insectivora  in  structure 
and  form,  as  their  common  ancestors,  and  these 
again  point  to  the  Marsupials,  we  can  assuredly 


LIVING  MAMMALIA  AND  THE1K  ANCESTORS.      85 

not  call  these  mixed  forms,  but  forms  bearing  the 
impress  of  different  circumstances. 

But  when  brought  into  this  connection  with 
the  primeval  world,  the  systematic  arrangement  of 
the  Mammalia — made  in  accordance  with  their 
present  state—  must  above  all  things  appear  alto- 
gether unsatisfactory.  The  Mammals,  as  the  most 
highly  developed  animals,  not  only,  of  course, 
stand  farthest  from  the  beginnings  of  animal  life, 
but  they  have  also — at  all  events  the  Vertebrates 
—  diverged  more  from  one  another  than  any 
other  class.  For  even  the  Keptiles,  whose  day  is, 
in  every  respect,  long  since  past,  are  behind  them 
in  this.  However  adaptable  their  limbs  were  to 
circumstances  (their  teeth  were  less  so),  their  brain 
remained  stationary.  It  was  only  with  the  charac- 
teristic advance  in  the  organisation  of  the  Mam- 
malia that  scope  was  given  to  a  progressive  brain. 
The  attempts  which  have  repeatedly  been  made  to 
make  use  of  this  point  also  for  a  systematic  arrange- 
ment of  the  Mammalia,  have  either  been  too  one- 
sided, or  could  not  show  any  satisfactory  result, 
owing  to  the  large  gaps  in  our  palaeontological 
knowledge.  It  is  reserved  for  the  future  to  make 
the  systematic  classification  of  the  Mammalia  a 
really  '  natural '  one,  and  one  which  shall  attain  the 


86  THE  MAMMALIA. 

goal  towards  which  Cuvier  and  Lamarck  paved  the 
way  with  their  grand  beginnings,  although  starting 
from  such  different  points  of  view.  Meanwhile 
•we  must  content  ourselves  with  following  the  old 
tracks. 

1.    THE    MONOTREMA,    CLOACAL    OR   FORKED   ANIMALS. 

An  example  as  to  how  the  animal  form  should 
not  be  conceived  is  given  by  Giebel,  a  man  of  vast 
knowledge  but  yet  opposed  to  the  theory  of  descent. 
He  says  of  the  two  well-known  species  of  this  group, 
the  Ant-eaters  (Echidna),  and  the  Duck-moles  (Orni- 
thorhyncha) :  '  If  there  is  anything  marvellous  about 
any  series  of  animal  forms,  the  Cloacal  animals  ap- 
pear the  strangest  of  all ;  for  the  irregularities  and 
wondrous  shapes  in  the  variously  formed  organisa- 
tions of  the  Edentata  are  far  surpassed  by  those 
met  with  in  the  Cloacal  animals.'  Brehm  also 
does  not  carry  us  much  farther ;  he  says :  '  The 
Ant-eater  and  the  Duck-mole  are  still  classed 
sometimes  with  the  Marsupials  and  sometimes 
with  the  Edentata.  And,  in  fact,  they  combine 
not  only  the  peculiarities  of  the  one  and  of  the 
other  class,  but  also  the  most  varied  and  opposite 
characteristics  of  the  whole  first-named  class  (the 
Mammals) ;  indeed,  they  seem,  to  a  certain  extent, 


THE  MONOTKEMA,   OR  CLOACAL  ANIMALS.      87 

to  be  the  connecting  links  between  the  Mammals, 
Birds,  and  Reptiles.'  That  he  should  regard 
them  as  connecting  links  is  certainly  somewhat  to 
the  point,  only  the  Birds  must  be  left  out  of  the 
question.  A  direct  connection  between  Bird  and 
Mammal  there  is  not ;  they  are  allied  through 
their  ancestors,  and  the  latter  stand  widely  sepa- 
rated, although  within  the  extremely  comprehensive 
order  of  Amphibio-reptiles. 

Their  beak- shaped  jaws  do  not  possess  any 
teeth;  only  in  the  case  of  the  Duck- mole  do  we  find 
a  few  horny  plates.  This  want  of  teeth  has  per- 
haps been  inherited  from  reptile-like  ancestors,  and 
must  have  been  distinct  from  the  ancestors  of  the 
toothed  mammals;  hence  it  would  be  a  case  of 
convergence.  The  possible  case  of  the  common 
origin  of  Duck-moles  and  of  Toothed  mammals  from 
primary  forms  of  toothless  animals,  and  of  the 
acquisition  of  teeth  by  Mammals  independent  of 
toothed  ancestors,  is  in  the  highest  degree  im- 
probable ;  or  else  the  loss  of  the  teeth  may  have 
occurred  only  at  a  later  period,  after  a  common 
origin  on  the  line  of  duck-moles,  as  in  the  case  of 
Birds  and  various  Edentates,  partially  also  in  the 
upper  jaw  of  the  Hoofed  Animals,  and  in  all  cases 
of  the  reduction  in  the  number  of  teeth.  We  take 


88  THE  MAMMALIA. 

all  these  possibilities   into   consideration   without 
gaming  anything  for  the  point  in  question. 

It  is,  however,  a  different  matter  with  the 
following  characteristics.  The  Cloacal  animals  are 
the  only  Mammals  where  the  collar-bones  have 
become  united  into  one  piece  by  means  of  the 
breast-bone,  as  in  the  case  of  the  well-known  fork- 
bone  in  birds.  In  all  other  Mammals,  including 
Man,  we  find,  in  place  of  this  free  os  coracoideum, 
a  short  hook,  the  crow-beak  bone.  This  circum- 
stance, in  and  of  itself,  might  lead  to  the  supposition 
that  the  Duck-moles  were  more  fully  developed  than 
the  other  Mammals.  However,  from  the  course  of 
the  development  as  a  whole,  it  is  obvious  that 
this  portion  of  the  shoulder  of  the  higher  Mam- 
mals must  be  regarded  as  a  case  of  reversion. 
Another  peculiarity  of  the  skeleton  of  the  Mono- 
trema  is  a  couple  of  bones  which,  turned  towards 
the  front,  rise  above  the  pubic  bones  at  the 
abdomen  side  of  the  pelvis.  These  bones  exist  also 
in  the  Marsupials.  As,  however,  we  are  uncertain 
about  their  origin  and  significance  even  in  the  case 
of  the  Marsupials,  nothing  much  can  be  made  out 
of  the  agreement.  Still,  the  occurrence  of  these 
bones  in  the  two  classes  points  to  a  close  relation- 
ship, 


THE  MONOTREMA,  OB  CLOACAL  ANIMALS.       89 

All  the  more  characteristic  is  another  peculiarity 
of  the  Monotrema :  the  urinary  and  genital  appa- 
ratus have  no  separate  openings,  but  one  opening 
in  common  with  the  intestinal  canal,  called  the 
cloaca.  This  stage  of  development  at  which  the 
Monotrema,  like  the  lower  Vertebrates,1  remain  all 
their  life,  is  an  embryonal  stage  in  the  case  of  all 
the  other  Mammals,  and  not,  as  Giebel  says,  an 
irregularity  or  singularity,  but  a  perfectly  normal 
inheritance.  In  the  other  Mammals  the  peculiarity 
exists  normally  as  a  transition  form,  but  after 
the  embryonal  life  it  is  a  condition  that  has  been 
overcome. 

That  the  Monotrema  possess  actual  lacteal 
glands  is  a  long-established  fact.  There  are  a 
number  of  separate  glands  from  which  the  milk 
issues,  not,  however,  from  a  teat  or  nipple,  but 
from  flat,  perforated  patches  of  skin.  These  were 
formerly  held  to  be  mucus-  or  perspiration  glands, 
but  are  now  recognised  as  an  actual  proof  for  the 
irrefutable  supposition  that  the  secretion  of  milk 
was  acquired  only  gradually.  Those  of  our  readers 
who  may  consider  this  idea— of  the  common  skin- 
glands  of  the  reptile-like  animals  having  in  the 
course  of  time  developed  into  the  important 

1  In  most  Fishes  these  arrangements  are  different. 


90  THE  MAMMALIA. 

mammary  glands — as  very  strange  and  but  little 
pleasant  one,  we  would  remind  of  the  case  of  the 
pigeons.  Pigeons  do  not  indeed  possess  glands 
on  the  outer  skin,  but  have  glands  developed  in 
their  crops  which  provide  the  young  with  food  ; 
whereas  in  the  other  birds  we  find  at  most  only 
secretions  for  softening  the  food  and  preparing  it 
for  digestion. 

Owing  to  the  fundamental  importance  of  the 
mammary  glands,  we  must  enter  somewhat  more 
fully  upon  the  subject  here,  while  discussing  the 
lowest  known  forms  of  Mammals.  The  simplest 
arrangement  is  that  of  the  Duck-mole,  such  as  was 
perhaps  inherited  from  unknown  ancestors,  but 
which  probably  also  represent  a  stage  of  reversion. 
It  is  different  with  the  Echidnas,  porcupine  ant- 
eaters.  We  here  find  the  perforated  glandular 
patch  lying  somewhat  deeper  and  surrounded  by  a 
circular  wall  of  skin.  In  this  so-called  mammary 
pouch  the  immaturely-born  offspring  finds  admis- 
sion and  protection,  and  by  sucking  forms  for  itself 
probably  a  temporary  pointed  teat.  The  most 
important  matter  is  that  the  formation  of  the  teat 
or  nipple  begins  in  all  the  other  Mammals  and  in 
Man  with  the  indications  of  this  kind  of  mammary 
pouch.  The  form  and  more  delicate  structure  of 


THE  MONOTREMA,   OR   CLOACAL  ANIMALS.       91 

the  outer  milk  apparatus  does  not  appear  to  have 
been  directly  transmitted  only  to  the  Marsupials  ; 
thus  the  various  formations  of  teats,  which  can  be 
traced,  from  those  first  beginnings,  amid  all  sorts 
of  modifications,  through  the  whole  series  of  the 
higher  Mammals,  also  corroborate  the  inductive 
proof  of  the  relationship  of  the  whole  mammal 
world  including  Man.1  And  even  in  this  case  the 
history  of  the  development  of  the  living  repre- 
sentative of  an  animal  group,  supplements  the  want 
of  observations  on  conditions  and  processes  that 
have  played  a  part  in  the  remote  period  of  the 
earth's  history. 

A  separate  origin  for  the  Monotrema  cannot  be 
unconditionally  rejected,  but  is  exceedingly  im- 
probable, if  only  on  account  of  the  perfect  agree- 
ment of  the  embryonal  mammary  apparatus  of  the 
Marsupials  and  of  the  other  orders,  with  the  mar- 
supial pouch  of  the  Echidnas.  The  suppositions 
favouring  the  possible  independence  of  the  Mono- 
trema do  not,  of  course,  possess  any  actual 
foundation  as  long  as  we  do  not  know  the 
amphibio-reptile  forms  where  the  mammal  charac- 
ter shows  the  first  signs  of  incoming  and  of 

1  Klaatsch,  '  Zur  Morphologic  der  Siiugethierzitzen '   (Hor- 
pholog.  Jahrbuch,  ix.  1883). 


92  THE  MAMMALIA. 

becoming  established.  On  the  other  hand,  to 
take  a  very  obvious  case,  when  competent  au- 
thorities emphasize  the  possibility  that  birds  of 
the  ostrich  species  (the  Katitae)  are  of  a  different 
reptile  origin  to  the  other  birds  —  e.g.  those  with 
a  keel-shaped  breast-bone— the  supposition  of  a 
convergence  would,  in  fact,  be  established ;  for  bird- 
like  peculiarities  are  met  with  in  the  skeleton  of 
several  fossil  groups  of  reptiles,  hence  the  trans- 
formation to  the  real  bird  would  in  various  respects 
be  absolutely  no  wonder  at  all. 

The  geographical  distribution  of  the  Monotrema 
is  confined  to  South  Australia  and  Tasmania.  But 
a  few  years  ago  a  new  species  of  Ornithoryncha 
was  described  from  a  perfect  skull  found  in  New 
Guinea.  This  does  not  really  make  the  range  of 
their  distribution  any  larger,  as  New  Guinea  was 
clearly  at  one  time  connected  with  the  continent  of 
Australia,  and  consequently  belonged  to  the  same 
zoological  province.  Not  a  trace  of  any  fossil 
discovery  leads  us  from  the  present  living  Mono- 
trema back  to  the  primeval  world,  to  which  never- 
theless they  stand  in  such  palpable  relation.  They 
are,  moreover,  widely  different  from  the  other 
groups  of  living  Mammals.  Even  admitting  the 
debatable  supposition  that  they  were  directly  allied 


THE  MAKSUPIALS,   OR  POUCHED  ANIMALS.      93 

to  the  Marsupials — hence  derived  from  common 
primary  forms — their  separation  from  these  must 
have  taken  place  before  the  Trias  period.1 

2.    THE   MARSUPIALS,    OB   POUCHED   ANIMALS. 

The  Marsupials  stand  in  a  remarkable  position 
between  the  Prototheria  (the  Monotrema)  and  the 
Eutheria  (the  '  higher  Mammals '),  but  obviously 
their  relation  to  the  latter  is  more  direct,  whereas 
the  gap  between  the  Monotrema  and  the  Mar- 
supials is  left  to  the  free  play  of  the  imagination. 
It  is  not  readily  intelligible  how  the  marsupial 
pouch  of  the  Echidna — which  serves  to  protect 
the  helpless  offspring— could  have  originated  by 
natural  selection.  Here  the  two  bones  rising  from 
the  pelvis,  the  ossa  epipubica,  transmitted  to  them 
by  their  ancestors  of  the  monotreme  species,  have 
been  brought  into  connection.  The  openings  of 
the  urinary  and  genital  organs  have  remained 
at  a  low  stage  and  show  resemblance  to  the 

1  For  the  sake  of  clearness  and  simplicity  we  intend  in  the 
following  pages,  with  Huxley,  to  call  the  Monotrema,  as  the  lowest 
Mammal  form,  Prototheria.  They  are  followed  by  the  Marsupials 
as  Metatheria ;  and  all  the  other  orders  comprised  as  the  '  higher 
Mammalia  '  then  follow  as  Eutheria.  Zoologists  will  know  that 
the  two  last  designations  stand  for  the  more  general  terms 
Didelphia  and  Monodelphia,  which,  however,  require  a  special 
explanation. 

10 


94  THE  MAMMALIA. 

arrangement  in  the  Monotrema.  The  young  leave 
the  maternal  womb  in  a  very  immature  state,  i.e. 
the  nourishment,  the  renewal  of  blood  in  the 
uterus  which,  in  the  case  of  the  Eutheria  (the 
high  Mammals)  is  regulated  by  means  of  the 
placenta  for  the  advantage  of  the  offspring,  must, 
owing  to  the  absence  of  this  foetal  organ,  be 
accomplished  at  an  early  stage  by  mammary 
glands.  The  further  development  of  teats,  in  ac- 
cordance with  a  beginning  corresponding  to  the 
marsupial  pouch  of  the  Echidna,  has  already  been 
mentioned. 

A  fresh  feature  by  which  the  Marsupials  are 
brought  into  direct  connection  with  the  higher 
Mammals  is  their  dentition.  And,  moreover,  with 
their  dentition  they  extend  back  beyond  the  Mono- 
trema to  primary  amphibian  forms,  and  at  the 
same  time  the  great  variety  of  the  forms  prove, 
in  a  most  obvious  way,  that  they  have  differen- 
tiated from  the  simpler  beginnings  of  their  ancestors, 
in  so  far  as  they  were  obliged  to  do  so  owing  to 
the  generally  more  uniform  surface  of  the  earth. 
One  peculiarity  affecting  the  whole  group  of  Mar- 
supials is  this,  that  only  one  pair  of  teeth  in  either 
jaw  is  changed  during  the  lifetime.  The  succes- 
sion of  the  teeth  with  the  incoming  of  the  one 


THE  MARSUPIALS,  OR  POUCHED  ANIMALS.      95 

deciduous  tooth,  is  not  a  safe  starting  point  for 
making  a  satisfactory  comparison  of  their  denti- 
tion with  that  of  the  Eutheria  (the  higher  Mam- 
mals). 

In  an  interesting  paper  on  the  classification  of 
the  Mammalia,  Huxley l  says :  '  As  Professor 
Flowers  has  pointed  out,  the  question  arises 
whether  we  have  here  a  primary  dentition  with 
only  one  secondary  tooth,  or  a  secondary  dentition 
with  only  one  tooth  of  the  primary  set  left.  I 
have  no  doubt  that  the  answer  given  to  this  ques- 
tion by  Prof.  Flowers  is  correct,  and  that  it  is 
the  milk  dentition  of  which  only  a  vestige  is  left 
in  Marsupialia.  Among  existing  Eodents,  in  fact, 
all  conditions  of  the  milk  dentition  exist  from  a 
number  equal  to  that  of  the  permanent  incisors  and 
premolars  (as  in  the  rabbit)  to  none  at  all.  The 
same  thing  is  observed  in  the  Insectivora,  where 
the  Hedgehog,  and  probably  Centetes,  have  a  full 
set  of  milk  teeth  while  none  have  yet  been  found 
in  the  Shrews.  In  these  cases  it  is  obvious  that  the 
milk  dentition  has  gradually  been  suppressed  in 
the  more  modified  forms ;  and  I  think  that  there 


1  '  On  the  Application  of  the  Laws  of  Evolution  to  the  Arrange- 
ment of  the  Vertebrata,  and  more  particularly  of  the  Mammalia ' 
(Kosmos,  ix.  1881). 


96  THE  MAMMALIA. 

can  be  no  reasonable  doubt  that  the  existing  Mar- 
supials have  undergone  a  like  suppression^  of  the 
deciduous  teeth  in  the  course  of  their  development 
from  ancestors  which  possessed  a  full  set.'  If  this 
is  the  right  explanation,  the  suppression  of  the 
milk  teeth  in  Marsupials  must  be  transferred  to 
a  comparatively  more  recent  period  when  the 
branching  off  of  the  Eutheria,  which  still  possess 
the  milk  teeth,  had  not  yet  taken  place.  A  proof 
of  this  is  that  some  groups  of  Mammals  do  not 
show  this  succession  of  milk  teeth  and  permanent 
teeth,  or  rather  that  they  have  lost  it  notwith- 
standing a  relationship  marked  by  a  change  of 
teeth. 

As  regards  teeth  and  limbs,  the  Marsupials 
of  to-day  bear  testimony  to  no  small  amount  of 
adaptability.  It  may  be  compared  with  that 
adaptability  which  is  evident  in  the  whole  class  of 
the  higher  Mammals,  if  we  are  not  to  admit  that 
the  Eutheria  have  originated  separately  in  groups 
from  the  already  modified  Metatheria.  True,  the 
most  useful  and  docile  Hoofed  Animals  are  looked 
for  in  vain  among  the  Marsupials,  and  notwith- 
standing the  great  diversity  in  the  formation  of 
their  teeth — which  goes  hand  in  hand  with  their 
mode  of  life— the  types  of  the  insect-,  flesh-,  grass- 


THE  MAKSUPIALS,  OR  POUCHED  ANIMALS.      97 

and  root- eating  Marsupials  are  far  more  alike  in 
structure  than  are  the  Eutheria  among  one  another. 
The  largest  numbers  of  teeth — fifty — is  found  in 
the  opossum,  Didelphyf.  The  marsupial  pouch — 
the  characteristic  feature  of  the  class — has,  it  is 
true,  become  reduced  to  a  few  unimportant  folds  on 
the  abdominal  skin.  Still,  because  of  the  number 
of  their  teeth,  and  because  the  earlier  fossil  Mam- 
malia show  most  affinity  to  them,  they  must  be 
regarded  as  the  least  modified  members  of  the 
family. 

The  Didelphidae,  or  Marsupial  Eats,  are  now 
confined  to  southern  and  central  America.  Neither 
geology  nor  palaeontology  gives  us  any  clue  as  to 
how  this  has  happened:  whether  and  when  this 
branch  separated  from  the  main  group  confined  to 
Australia :  whether  the  agreement  of  the  Didelphidae 
with  the  other  Marsupials  is  a  matter  of  converg- 
ence :  or  whether  the  Australian  Marsupials  are  of 
American  origin.  However,  we  shall  have  to  return 
to  this  latter  supposition  owing  to  an  anatomical 
peculiarity.  The  dentition  of  the  Marsupial  Eat 
shows  most  resemblance  to  our  Insectivora,  and  they 
also  agree  with  them  in  many  ways  as  regards  mode 
of  life  and  food.  Even  Cuvier  discovered  their  fossil 
remains  in  the  Eocene  strata  of  Paris.  It  was  only 


98  THE  MAMMALIA. 

at  a  much  later  date  that  E.  Owen l  traced  similar 
animals  back  to  the  Trias  formation. 

In  the  so-called  Ehaetic  beds,  one  of  the  sections 
of  the  Trias,  a  few  minute  teeth  were  found  which 
probably  belonged  to  an  Insectivorous  Marsupial ; 
these  teeth  have  given  rise  to  the  genus  Microlestes. 
Again,  in  the  Lower  Lias  (of  the  Jura  formation), 
fragments  of  lower  jaws  have  been  found  that  must 
be  regarded  as  belonging  to  small  Insectivorous 
Marsupials.  Phascolotherium  is  most  frequently 
mentioned.  Similar  remains  are  found  in  the  strata 
directly  below  the  Chalk  formations,  and  among 
these  we  have  Plagiaulax,  very  remarkable  on 
account  of  the  reduction  and  specialisation  of  its 
dentition.  In  Fig.  2  we  have  the  lower  jaw  of  PL 
minor  (A)  in  natural  size.  Hence  it  was  an  animal 
of  the  size  of  a  mouse.  In  the  enlarged  jaw  of 
another  species  (Fig.  2,  B)  the  premolar  (?),  marked 
by  number  4,  and  followed  by  two  molar-shaped 
teeth,  shows  the  very  marked  character  of  the 
genus,  which  is  less  distinct  on  the  preceding 
teeth — i.e.  the  deep  diagonal  grooves. 

Owen  looks  upon  all  these  imperfect  remains  as 
'  generalised  forms,'  whereas  Huxley  asks,  what  are 

1  Owen,  '  Monography  of  the  Fossil  Mammalia  of  the  Mesozoio 
Formation  '  (Palceontological  Society,  1871). 


THE  MARSUPIALS,  OR  POUCHED  ANIMALS.      99 

the  peculiarities  of  the  more  embryonal  or  less 
specialised  type  of  the  Phascolotherium  as  compared 
with  the  Opossum  of  to-day.  Upon  the  whole  Owen 
seems  to  us  to  be  right,  as  regards  the  dentition, 
in  coming  to  the  conclusion  that  from  Phasco- 
lotherium to  Didelphys  we  have  an  advance  from 
the  generalised  to  the  specialised  form.  This  sup- 
position cannot,  however,  be  extended  to  Plagiaulax. 


FIG.  2. 

A.  Lower  Jaw  of  Plagiaulax  minor.    Natural  size. 

B.  Lower  Jaw  of  PL  medius.    Pour  times  enlarged. 

This  animal  appears  rather  to  be  already  so  far 
specialised  that  it  advanced  but  little  farther  in 
subsequent  times;  nay,  if  the  line  were  carried 
down  to  the  actual  present,  it  might  even  be  said 
to  have  become  effaced. 

The  remains    found   of    Plagiaulax  show   the 
following  connection  with  the   living  Marsupials. 


100  THE  MAMMALIA. 

An  animal  allied  to  the  European  Plagiaulax  is 
described  by  Marsh  from  the  Jura  of  Wyoming — 
Ctenacodon  —  without  the  above-mentioned  deep 
grooves  on  the  premolars,  but  they  are  jagged  on 
the  upper  edge.1  In  addition  to  this,  in  1883 
a  discovery  of  great  interest  was  made,  by  which 
the  connection  between  the  primary  and  the  exist- 
ing Marsupials  has  been  almost  directly  restored. 
In  the  Lower  Eocene,  in  the  neighbourhood  of 
Bheims,  Lemoine  found  the  jaw  of  an  animal  which 
shows  a  remarkably  grooved  tooth  as  the  only  pre- 
molar,  and  behind  it  two  low  tuberculate  molars 
(Fig.  3,  A).  Owing  to  its  close  resemblance  Lemoine 
called  it  Neoplagiaulax,  and  classes  it  by  the  side  of 
the  existing  dwarf-kangaroo  of  Australia,  the  Bet- 
tongia  penicillata  (Fig.  3,  B).  This  latter  also  has 
a  grooved  tooth,  even  though  somewhat  less  deeply 
marked. 

As  the  Eocene  animal  has  two,  and  Bettongia 
three  teeth  behind  the  grooved  tooth,  we  cannot,  of 
course,  speak  of  any  direct  relationship,  but  we 
may  assume  a  lateral  connection  between  the  two. 

1  We  shall  here  use  the  words  premolars  and  molars  (as  most 
palaeontologists  do),  although  according  to  the  conditions  of  the 
living  Marsupials,  we  are  not  absolutely  certain  whether  we  are 
right  in  distinguishing  the  teeth  of  the  fossil  forms  as  milk  and 
permanent  teeth,  premolars  and  molars. 


THE  MARSUPIALS,   OR  POUCHED  ANIMALS.    101 

Lemoine  also  finds  agreements  between  Plagiaulax 
and  Microlestes,  and  has  thus  lengthened  the  series 
from  the  Present  to  the  Trias  formation.  The 
French  zoologist  further  discovers  in  the  upper 
cheek-teeth  of  the  Brown  Eat  similarities  with 
teeth  which,  found  isolated,  probably  belong  to 


FIG.  3. 

A.  Lower  Jaw  of  Neoplagiaulax. 

B.  Lower  Jaw  of  Bettongia  penicillata.    After  Lemoine. 

Plagiaulax.  All  this  points  to  the  primeval  stock 
where  Marsupials,  Insectivora,  and  Eodents  meet. 
But  we  cannot  imagine  that  Plagiaulax  was  an 
insect-eater ;  I  should  be  inclined  rather  to  assume 
that  Bettongia  lived  upon  vegetable  food. 

The  scientific   dispute   regarding  the  mode  of 


102  THE  MAMMALIA. 

life  of  Plagiaulax — as  expressed  by  its  dentition — 
which  has  been  carried  on  with  much  animation, 
more  particularly  by  English  enquirers,  also  affects 
a  Marsupial  of  the  Diluvium ;  and  Owen  has  ex- 
pressed his  conviction  as  to  the  carnivorous  habits 
of  the  animal  (which  is  almost  the  size  of  a  lion) 
by  the  name  he  gives  to  it,  i.e.  Thylacoleo  carnifex. 
Its  skull,  like  that  of  many  of  the  Marsupials, 
shows  the  peculiarity  of  strongly  developed  middle 
incisors.  The  canines  and  front  cheek-teeth  are  very 
insignificant.  But  both  above  and  below  follows 
a  huge,  compressed  premolar  which  involuntarily 
reminds  us  of  the  canine  of  the  large  cats  of  our 
day.  The  rest  of  the  back  teeth,  also,  do  not  op- 
pose the  supposition  of  its  being  carnivorous,  hence 
here  again  we  do  not  understand  Owen's  learned 
opponent  who  would  characterise  Thylacoleo  as  a 
plant-eater.  We  agree  with  Owen's  opinion  that 
none  of  the  existing  Carnivorous  Marsupials  show 
a  similar  concentration  of  the  dentition — such  a 
good  or  serviceable  set  of  teeth— as  Thylacoleo,  in 
whose  case  this  direction  of  development  has  ex- 
hausted itself.  But  does  our  Marsupial  Lion  show 
affinity  with  Plagiaulax,  as  Cope  would  have  us 
believe?  Quite  apart  from  the  question  of  food, 
we  consider  a  transition  from  the  dentition  of 


THE  MAKSUPIALS,  OR  POUCHED  ANIMALS.    103 

Plagiaulax  to  that  of  Thylacoleo  as  exceedingly 
improbable ;  besides  this,  the  discovery  of  the 
Neoplagiaulax  leads  us  to  an  entirely  different 
track  from  Plagiaulax. 

The  Marsupial  Lion  of  the  Australian  Pleisto- 
cene takes  us  back  to  the  time  when  the  group  had 


Fia.  4. — Skull  of  Diprodon  Australia.    One-tenth  natural  size. 
After  Owen. 


reached  its  fullest  development  (followed  by  a  some- 
what rapid  decline),  and  which  presupposes  a  similar 
and  contemporaneous  abundance  of  plant-eaters 
necessary  for  the  sustenance  of  the  huge  flesh- 
eaters.  And  there  exists  at  least  one  species  of 
those  theoretically  required — the  colossal  Dipro- 


104  THE  MAMMALIA. 

todon  australis,  whose  skull  is  one  metre  in 
length.  It  was  obviously  a  plant-eater  with  a 
specialised  dentition,  as  is  proved  by  the  peculiar 
incisors  and  the  compressed  cheek-teeth,  which  are 
separated  from  the  incisors  by  a  considerable  gap. 
According  to  Owen's  masterly  comparisons,  in 
Cuvier's  style,  Diprotodon  was  a  gigantic  kangaroo, 
but  without"  the  power  of  leaping.  Like  most  of 
the  primeval  species  which  attained  an  unusual 
development  of  strength  and  a  certain  monstrosity 
of  form,  it  has  not  left  any  direct  descendants,  but 
together  with  it  there  lived,  in  those  days,  powerful 
creatures  closely  related  to  the  kangaroos,  such  as 
Palorchestes,  with  a  skull  40  cm.  in  length. 

Wombats  also  (Phascolomys),  of  which  there 
exist  only  a  few  species,  find  their  fossil  com- 
pletion in  numerous  species  of  this  genus,  and 
partly  corresponded  with  them  as  regards  size,  and 
partly  far  surpassed  *  them.  They  appear  all  to 
have  been  root-eaters,  and,  as  is  well  known,  the 
habitus  of  the  Eodents  is  repeated  in  a  remarkable 
manner  within  the  group  of  Marsupials.  The  one 
that  can  most  readily  be  compared  with  them  is 
the  Nototherium,  which  again  is  a  creature  that  far 
exceeds  the  living  species  in  size,  with  a  skull  of 
the  most  ugly  description  imaginable.  While  the 


THE  MARSUPIALS,   OR  POUCHED  ANIMALS.     105 


FIG.  5.— Skull  oi  the  Wombat  (Phascolarctus  fuscus).     One-half 
natural  size.    After  Owen. 


FIG.  6. — Skull  of  Nototherium,  from  the  side.     One-sixth  natural 
size.     After  Owen. 


11 


106  THE  MAMMALIA. 

Phascolarctus  fuscus  of  the  present  day  (Fig.  5) 
shows  a  skull  of  19  cm.,  the  skull  of  Notothe- 
rium  Mitchelli  (Figs.  6  and  7)  is  46 J  cm.  long,  to 
40J  cm.  broad.  The  breadth  is  caused  by  the 
enormous  arch  of  the  cheek-bone.  The  cheek-teeth 


FIG.  7.— Skull  of  Nototherium,  front  view.     One-sixth  natural 
size.    After  Owen. 

are  very  like  those  of  Diprotodon,  and  are  likewise 
furnished  with  transverse  ridges,  the  whole  dental 

O  f\  K 

formula  being  the  same  :  i  -  c  -  m  ~.  The  struc- 
ture and  form  of  the  teeth  point  to  a  plant-eater, 
and  not  to  the  habits  of  a  wombat  that  grubs  for 
roots. 


THE  MARSUPIALS,   OR  POUCHED  ANIMALS.     107 

All  of  the  above-mentioned  fossil  Marsupials, 
which  have  been  described  by  Owen  in  his 
masterly  work,1  belong  to  the  most  recent  geological 
past.  They  are  found  principally  in  Eastern  and 
South-eastern  Australia,  partly  in  river-beds — 
as  for  instance  in  that  of  the  Condamine  and 
its  tributaries — and  in  the  dried-up  deposits  of 
fresh  waters,  partly  also  in  caves.  The  so-called 
Darling  Downs,  not  far  from  the  Condamine,  have 
yielded  a  great  number  of  these  fossils.  It  was 
here  that  Leichhard,  among  others,  collected  at 
the  commencement  of  his  journey  the  remains  of 
the  Diprotodon,  and  considered  them  so  little  like 
fossils,  that  he  expressed  the  hope  that  he  would 
meet  with  living  specimens  of  the  same  animals  in 
the  interior  of  the  continent. 

In  conclusion,  we  come  again  to  the  question 
as  to  the  relation  between  the  American  and  the 
Australian  Marsupials,  with  regard  to  which,  as 
has  already  been  said,  the  primitive  earth  gives 
us  no  clue.  Several  peculiarities,  more  particu- 
larly the  completeness  of  the  dentition,  point  to 
the  Didelphidae  as  the  earlier  branch.  But  there 
is  also  another  circumstance.  According  to  Bar- 
Owen,  Extinct  Mammals  of  Australia  (London,  1877),  with 
131  plates. 


108  THE   MAMMALIA. 

deleben's  recent  observations  on  the  structure  of 
the  tarsus  or  root  of  the  foot  in  mammals  and  in 
Man,1  the  Didelphidse  herein  show  most  agreement 
with  the  Lower  Vertebrates.  All  the  American 
Marsupials  (the  number  of  which  has  been  con- 
siderably increased  by  the  researches  of  Hensel,  who 
died  at  too  early  an  age)  possess  the  determining 
bones  which,  it  is  true,  are  not  altogether  wanting 
in  the  Australian  species,  but  are  very  much  modi- 
fied, and  thus  point  to  a  later  differentiation.  All 
of  the  American  species,  says  Bardeleben,  are  five- 
toed.  The  larger  forms,  also  those  without  the 
isolated  bony  intermedium,  and  finally  those  with 
a  reduced  metatarsus,  are  all  found  in  Australia. 
For  this  reason  Bardeleben  thinks  himself  justified 
in  maintaining  it  to  be  probable  that  America,  and 
not  Australia,  was  the  primeval  home  of  the  Mar- 
supials. Hence,  that  the  Australian  Marsupials 
differentiated  after  the  continent  became  separated 
from  the  rest  of  the  earth,  and  that  they  there  be- 
came to  a  certain  extent  fixed  forms. 

If  the  enormous  area  of  the  Australian  con- 
tinent— of  which  Tasmania,  New  Zealand,  and  New 

1  Bardeleben,  '  Ueber  das  intermedium  tarsi '  (Sitzungsbe- 
richte  der  Jenaischen  Gesellschaft  filr  Medicin  und  Naturwissen- 
schaft,  1883). 


THE  MARSUPIALS,  OE  POUCHED  ANIMALS.     109 

Guinea  form  a  part,  and  which  is  so  poor  in  Mam- 
mals—be compared  with  any  other  corresponding 
latitudes,  the  contrast  in  the  fauna  will  appear  most 
striking.  The  eminent  German  naturalist  Carl 
Bitter,  in  his  lectures  on  Australia,1  was,  if  I  am  not 
mistaken,  the  first  to  describe  this  continent — not, 
as  is  usually  done,  as  the  '  latest,'  but  as  the  '  sta- 
tionary '  continent,  and  as  old-fashioned  both  as 
regards  fauna  and  flora.  This  uniformity  resulted 
in  an  entire  absence  of  the  most  important  outward 
inducement  to  the  formation  of  varieties  :  with  a 
moderate  struggle  for  existence,  a  consequently 
smaller  progress  in  the  functions  of  the  organisms. 
No  Marsupial  has  shown  itself  suitable  as  a 
domestic  animal ;  neither  work,  nor  protection, 
nor  milk  has  been  obtained  from  them.  Their 
flesh  only,  which  is  unpalatable  to  a  refined  taste, 
was  made  use  of  by  the  nomadic  primeval 
inhabitants;  the  latter  were  a  very  low  race  of 
men  who,  in  fact,  could  not  advance  beyond  the 
threshold  of  civilisation,  because  neither  the  neces- 
sity for  settling  in  certain  localities  (which  goes 
hand  in  hand  with  the  taming  and  training  of 
animals),  nor  any  inducement  to  cultivate  the  land, 
was  ever  brought  before  them. 

1  Which  lectures  I  had  the  good  fortune  to  attend. 


110  THE  MAMMALIA. 

3.   THE    EDENTATA,    OR   ANIMALS    POOR   IN   TEETH. 

Gaudry  tells  us  that  the  famous  brain-anatomist, 
Gratiolet,  compared  the  Sloths  to  old  men  crawling 
along  heavily,  with  hands  that  had  become  im- 
movable, and  as  having  lost  their  teeth  all  but 
a  few  pieces  of  cheek-teeth.  Now  if  we  take 
these  sloths  in  connection  with  the  Ant-eaters, 
Armadilloes,  and  scaly  ant-eaters  (which  call  forth 
similar  comparisons),  and  then  endeavour  to  de- 
termine the  common  character  of  the  strange 
company  from  a  scientific  point  of  view,  we  shall 
find  it  easier  to  ask  the  question  than  to  give  a  reply. 
It  is  true  that,  as  their  systematic  name  indicates, 
all  are  poor  in  teeth — i.e.  have  an  impoverished 
set  of  teeth,  some  even  no  teeth  at  all,  and  in  most 
cases  only  pointed,  regularly  formed  cheek-teeth 
without  enamel;  again,  all  possess  limbs  with 
large  claws;  further,  the  brain  is  in  all  cases  of 
very  moderate  size,  the  surface  of  the  larger  hemi- 
sphere being  flat.  However,  this  latter  peculiarity 
is  met  with  in  other  of  the  lower  orders  of  the 
Mammalia,  and  upon  a  closer  examination,  not 
much  importance  can  be  attached  to  the  certain 
amount  of  uniformity  of  the  toes  mentioned  above. 
One  sloth  has  three,  another  two,  the  Giant  Sloths 


THE  EDENTATA,   OB  ANIMALS  POOK  IN  TEETH.    Ill 

three  and  four  toes,  the  Ant-eaters  and  Armadilloes 
mostly  five  on  the  front  limbs ;  some  are  burrowers, 
some  climbers,  some  walk  upon  the  soles  of  their 
feet,  others  on  the  outer  sides  of  their  feet;  the 
Sloths  and  Ant-bears  have  hairy  coverings,  whereas 
the  Armadilloes  and  Scaly  Ant-eaters  are  covered 
by  an  armour  of  bone,  horn,  or  scales.  The 
armadilloes  and  ant-eaters  live  on  worms  and 
insects,  the  sloths  are  decided  plant-eaters. 

Even  from  a  superficial  consideration  like  this, 
it  is  evident — and  a  careful  study  of  the  question 
only  corroborates  the  remark — that  the  living  Eden- 
tata stand  in  a  wholly  different  relation  among  one 
another  from  that  of  the  members  of  other  orders 
of  animals,  with  the  exception,  perhaps,  of  the  Mar- 
supials and  Semi-apes.  The  certain  something  by 
which  they  are  connected,  but  which  our  system 
of  arrangement  cannot  specify  in  a  few  brief  or 
clear  words,  could  not  be  definitely  stated  unless 
we  were  acquainted  with  the  early  history  of  the 
group. 

Unfortunately,  we  do  not  know  their  early 
history.  Even  the  geographical  distribution  of 
the  few  existing  species  points  to  a  very  remote 
period.  Were  we  to  assume  that  the  ancestors  of 
the  Asiatic  and  African  Armadilloes,  the  African 


112  THE  MAMMALIA 

Ground-pig,  and  the  American  Ant-bears,  Sloths, 
and  Girdled- animals  were  at  one  time  allied,  we 
should  also  have  to  assume  a  connection  between 
the  three  continents.  There  has  been  no  lack  of 
very  bold  combinations  to  bridge  over  the  gap  to  our 
undiscoverable  friends — who,  it  is  to  be  hoped,  were 
better  equipped  for  a  wandering  life  than  they  are 
nowadays,  and  have  been  since  the  Tertiary,  at 
least — and  also  to  the  ostriches,  which,  owing  to  a 
similar  geographical  distribution,  are  equally  enig- 
matical. But  geology  has,  as  yet,  not  been  able  to 
say  her  yea  to  this.  America  alone  shows  a  rich  past 
for  the  Edentata  of  the  earth's  most  remote  periods. 
In  Europe  traces,  at  least,  have  been  found  which 
justify  the  conclusion  that  where  single  individuals 
of  the  modified  forms  lived,  others  also  of  the  sanie 
group  must  have  existed  contemporaneously  or  in 
the  preceding  periods. 

The  comparatively  large  variety  of  Edentates 
in  South  America  is  accounted  for  by  the  still 
larger  number  of  Diluvial  species,  some  of  which 
were  of  gigantic  size.  Many  inhabited  the  same 
tracts  of  land  which  are  at  present  the  abode 
of  their  evident  successors,  if  not  descendants. 
Others  we  find  pushed  farther  northwards,  but  we 
cannot  with  certainty  determine  whether  their 


THE  EDENTATA,   OR  ANIMALS  POOR  IN   TEETH.   113 

nearest  relatives,  in  those  clays,  lived  in  the  southern 
centre  of  distribution — where  they  continue  to  live 
up  to  the  present  time — or  whether  the  migration 


Fio.  8.— Skull  of  the  Giant  Sloth.     One-tenth  nat.  size. 
After  d'Alton. 

from  the  north  southwards  was  the  origin  of  the 
present  distribution. 

The  limbs  of  our  present  leaf-eating  Sloths  are 
most  perfectly  adapted  for  clutching  hold  of   the 


114  THE  MAMMALIA. 

branches  of  trees,  and  the  animals  are,  by  a  peculiar 
arrangement  in  the  circulation  of  their  blood,  en- 
abled to  remain  hours  and  days  in  the  most  un- 
comfortable positions ;  hence  they  have  almost  com- 
pletely lost  the  faculty  of  moving  along  level  ground. 
The  nearest  relatives  of  the  Sloth — i.e.  of  the 
genera  Bradypus  and  Choloepus — are  the  colossal 
Megatherium  and  Mylodon,  found  in  the  Diluvial 
deposits  of  North  and  South  America.  Of  the 
former  we  have  an  account,  with  illustrations,  in 
E.  d'Alton's  '  Classic  Monographies,'  where  it  is 
called  '  the  giant  sloth.'  He  there  says,  that,  com- 
pared with  its  skeleton  of  fourteen  feet  in  length  and 
seven  feet  high,  that  of  the  rhinoceros  appears  grace- 
ful, the  elephant  light  and  slim,  and  the  hippo- 
potamus of  good  proportions.  Its  unusually  broad 
and  bulky  body  has  a  very  small  skull  (Fig.  8),  and 
is  remarkably  like  that  of  our  present  S]oth.  True, 
the  cheek-bone,  which  in  the  case  of  the  Giant 
Sloth  is  firmly  attached  to  the  temporal  bone,  is 
not  thus  joined  in  our  present  Sloth  (Fig.  9),  but 
in  the  case  of  both  the  cheek-bone  shows  a  strongly 
developed  continuation  that  points  downwards.  The 
teeth  of  the  fossil  animal,  sixteen  in  number,  are 
compressed  within  the  actual  region  of  the  cheek;  in 
the  existing  species  they  stand  more  apart ;  but  in 


THE  EDENTATA,  OR  ANIMALS  POOR  IN  TEETH.  115 

both  they  bear  witness  to  the  peaceful  habits  of  a 
pi  ant- eater,  and  the  unmistakable  agreement  in  the 
type  of  skull  leaves  but  little  space  for  a  brain, 
even  in  the  Giant  Sloth. 

But  what  a  difference  in  the  limbs !     Of  the 
character  of  these  limbs  in  the  two  species,  Mega- 


FIG.  9.— Skull  of  the  Three-toed  Sloth.     Nat.  size. 

therium  and  Mylodon,  and  of  the  mode  of  life  of 
these  animals  as  it  has  to  be  imagined  from  the 
limbs,  Owen  gives  an  admirable  account.  We  will 
here  quote  his  description  of  the  Primeval  Sloths 
which  supplements  our  knowledge  of  the  nature 
and  habits  of  the  living  species,  even  though  it 
may  not  give  any  direct  explanation  of  them. 


116  THE  MAMMALIA. 

After  a  detailed  account  of  the  various  parts  of  the 
limbs,  he  says  :  '  The  principle  of  viewing  structures 
and  instruments,  in  reference  to  the  work  that  they 
do,  is  shown  to  be  good  in  gaining  insight  into  the 
mode  of  life  of  extinct  animals,  in  a  striking  degree 
through  its  application  to  the  skeletons  of  the 
M'egatheriods  (Giant  Sloths).  The  teeth  of  these 
conform  so  closely  in  all  characters  with  those  of 
the  Sloths  as  to  suggest  leaves  rather  than  roots  to 
have  been  their  food.  In  the  light,  slender  Sloths 
the  modifications  of  structure  for  climbing,  cling- 
ing, and  living  altogether  in  trees  are  carried  out 
to  an  extreme.  In  the  colossal  extinct  kinds,  the 
foliage  was  obtained  in  a  different  way.  The  huge, 
single  claw  on  the  hind  foot l  would  be  applicable 
as  a  pickaxe  to  clear  away  the  soil  from  between 
the  ramifications  of  the  roots :  a  second  claw 2  would 
have  interfered  with  such  work.  The  foot  is 
organised  to  give  great  strength  to  that  claw; 
dislocation  of  its  toe  is  specially  guarded  against ; 
the  rest  of  the  tarso-metatarsal  structure  relates 
to  the  power  of  the  foot  to  sustain  superincumbent 
pressure,  with  a  position  of  the  claw  bringing  its 

1  This  is  the  claw  of  the  middle  toe.     The  other  toes  appear 
to  have  been  furnished  with  a  kind  of  hoof. 

2  The  reader  who  finds  this  explanation  somewhat  too  odd 
not  forget  that  Owen  is  a  decided  teleologist. 


THE  EDENTATA,   OK  ANIMALS  POOE  IN  TEETH.  117 

side  instead  of  its  point  in  contact  with  the  ground. 
The  bones  of  the  thigh  and  leg  are  remarkable  for 
their  massive  proportions,  for  their  thickness,  and 
especially  their  breadth  in  proportion  to  their 
length :  the  femur  in  both  Mylodon  and  Megathe- 
rium would  rank  rather  with  the  "  flat  "  than  with 
the  "  long  "  bones.  These  osseous  columns  were 
needed  to  support  the  huge,  heavy,  expanded 
pelvis.  The  iliac  expansions  are  the  chief  con- 
ditions of  the  other  characteristics  of  this  part; 
and  they  are  unintelligible  save  in  relation  to  ade- 
quate extent  of  powerful  muscles,  especially  those 
arising  from  the  crista  ilii,  the  chief  of  which 
muscles  concentrate  their  force  upon  the  fore 
limbs.  This  indicates  that  these  limbs  were  put 
to  some  unusual  work  ;  and  the  inferences  from  the 
teeth  and  the  hind  claw  lead  to  its  recognition  as 
the  pulling  down  trees  and  wrenching  off  their 
branches ;  but  for  these  operations  the  pelvis  must 
have  adequate  fixity,  and  to  the  weight  and  strength 
of  itself  and  its  supporting  limbs  there  is  added  a 
tail  so  developed  as  to  serve  as  a  third  support  and 
give  the  pelvis  the  basis  of  a  tripod.  Without  this 
view  of  the  function  of  the  hind  parts  of  the 
skeleton,  we  can  only  see  that  the  pelvis  is  so  great 
and,  with  its  caudal  appendage,  so  weighty  as  to 
12 


118  THE  MAMMALIA. 

require  the  massive  proportions  and  structure  of 
the  hind  limbs,  and,  reciprocally,  that  these  be- 
speak a  proportionate  size  and  weight  of  the  parts 
to  be  sustained;  but  why  such  development  of 
sustaining  limbs  and  parts  to  be  supported  in 
reference  to  any  other  action  and  way  of  life  is 
inconceivable.  The  excess  of  bone  in  the  hind 
part  of  the  skeleton  once  recognised  as  relating  to 
the  fixed  point  of  attachment  of  muscular  forces 
working  the  fore  limbs — to  the  exertion  of  power 
adequate  to  prostrate  a  tree — and  the  rest  of  the 
bony  organisation  becomes  intelligible.  That  of 
the  hind  foot  has  been  explained  :  the  concomitant 
extent  of  the  muscular  origin  afforded  by  the  broad 
scapular  plate,  with  its  many  ridges,  crests,  and 
processes,  is  thereby  accounted  for.  The  necessity 
of  the  firmness  imparted  to  the  shoulder  joints  by 
the  perfect  clavicles  abutting  at  one  end  against 
a  large  "  manubrium,"  at  the  other  end  against  the 
conjoined  acromion  and  coracoid,  becomes  obvious. 
The  fore  foot  retained  three  huge  claws  to  effect  an 
adequate  grasp  of  the  trunk  or  bough :  for  their 
due  and  varied  application  the  fore  arm  enjoys  all 
the  variety  and  freedom  of  movements  which  an 
arm  terminated  by  a  hand  possesses.  A  tree  being 
prostrated  and  its  foliage  thus  brought  within 


THE  EDENTATA,   OR  ANIMALS  POOR  IN  TEETH.    119 

reach,  every  indication  in  the  skull  of  the  size, 
strength,  flexibility,  and  prehensile  power  of  the 
tongue  harmonises  with  the  foregoing  teleological 
conclusions.  The  Megatherioids,  like  the  giraffe, 
thus  plucked  off  the  foliage  on  which  they  fed. 
In  the  ridged  crowns  of  the  grinders  of  the  Giant 
Ground-Sloth  we  discern  the  power  of  crushing 
coarser  parts — a  greater  proportion  of  twigs  and 
stems,  e.g.  of  the  foliage,  than  the  diminutive  Tree- 
Sloths  take.  It  needed  only  evidence  of  the  occa- 
sional occurrence  of  what  might  happen  to  a  beast 
in  the  fall  of  a  tree  which  it  had  uprooted,  to  seal 
the  foregoing  physiological  inferences  with  the 
stamp  of  truth :  and  the  skeleton  of  the  Myloclon 
in  the  Hunterian  Museum  shows  that  evidence 
above  the  right  orbit  and  at  the  back  part  of  the 
cranium.' 

Those  who  can  agree  with  Owen's  whole  deduc- 
tion as  to  the  tearing  down  of  trees  will  also  accept 
his  ingenious  explanation  of  the  cracks  in  the  skull 
of  the  famous  specimen  in  the  Hunterian  Collection 
of  the  College  of  Surgeons. 

But  although  this  account  and  our  observations 
concerning  the  existing  Bradypodae  throw  light 
on  the  structure  and  habits  of  the  fossil  group, 
they  do  not  tell  us  anything  about  the  real  an- 


120  THE  MAMMALIA. 

cestors  of  the  living  Brazilian  Sloths.  The  ex- 
pression so  frequently  used  in  illustrating  the 
relation,  that  the  sloths  of  the  present  day  are  the 
pygmean  remains  of  the  family  which  attained  a 
colossal  development  in  the  Diluvium,  would  be 
wholly  misunderstood  were  we  to  regard  the 
Bradypodae  as  crippled  Megatherioids  which  had 
taken  refuge  in  trees.  In  both  cases  the  limbs 
have  attained  extreme  formations  which  exclude 
every  thought  of  their  having  been  transmitted  the 
one  to  the  other ;  and  we  are  again  referred  to  a 
primary  form  that  lies  beyond  all  the  palseonto- 
logical  discoveries  yet  made. 

The  existing  Girdled- animals  and  the  Diluvial 
Glyptodons  resemble  one  another  less  in  structure 
than  in  size.  But  also  in  the  group  of  the  burrow- 
ing and  grubbing  Armadilloes  (which  live  on  worms 
and  insects)  one  is  tempted  to  set  too  little  value 
upon  the  length  of  time  necessary  for  their  origin 
than  a  careful  consideration  of  the  divergences 
would  warrant.  Thus  the  Girdled-mouse,  Chlamy- 
dophorus,  a  native  of  La  Plata,  differs  so  much 
from  the  girdled- animal  proper,  the  Dasypus,  in 
spite  of  the  most  obvious  relationship,  that  there 
must  be  between  them  a  whole  series  of  transitions ; 
and  hence  probably  one  or  two  geological  periods 


THE  EDENTATA,   OR  ANIMALS  POOR  IN  TEETH.   121 

between  them  are  necessary  for  the  development 
of  these  transitions. 

In  order  to  arrive  at  a  right  estimation  of  this 
and  of  all  the  other  similar  cases  which  we 
shall  have  to  allude  to  later,  it  will  be  well  to 
explain  our  views  by  a  graphic  example.  Let  us 
suppose  that  there  existed  by  the  side  of  our 
present  one-toed  horse,  a  three-toed  form — like 
that  of  Hipparion — which  possessed,  in  addition 
to  the  middle  toe  (corresponding  with  the  horse's 
toe),  other  two  toes,  smaller,  withdrawn  from  the 
ground  and  which  had  reached  a  stage  of  entire 
disuse.  This  is  by  no  means  a  capricious  idea. 
For,  in  the  same  way  as  '  circumstances '  led  to 
the  disappearance  of  the  one-toed  horse  in  America, 
circumstances  might  have  preserved  the  three-toed 
form  in  Asia  or  Europe,  somewhere  by  the  side  of 
the  races  that  were  being  transformed  into  a  one- 
toed  family.  But  even  granting  the  existence  of  a 
three-toed  animal,  a  non-scientific  person  would 
scarcely  realise  the  length  of  time  necessary  for  the 
deviation  and  for  the  formation  of  the  existing  form 
of  horse.  Hipparion  disappeared  from  the  scenes  as 
early  as  the  Upper  Miocene,  and  yet  our  horse  was 
not  what  he  now  is,  immediately  before  our  present 
geological  formation,  as  is  proved  by  the  order  for- 


122  THE  MAMMALIA. 

merly  considered  identical  with  it,  and  described 
under  the  name  of  Equus  Stenonis.  This  matter 
we  shall  have  to  enter  upon  more  fully  in  a  subse- 
quent chapter.  Although  not  extending  farther 
back  than  to  the  Miocene,  the  period  necessary  for 
this  reduction  of  the  two  toes  and  of  the  meta- 
tarsals  to  last  rudiments  (splint  bones),  was  one  of 
enormous  length.  And  yet  the  modifications  that 
took  place  during  that  period  in  the  horse's  foot, 
and  the  transformation  of  the  dentition  that  accom- 
panied the  modifications  of  the  foot,  were  but 
trifling  compared  with  the  differentiations  in  the 
group  we  are  at  present  discussing  (the  Edentata). 
There  is  one  other  point  to  consider  as  regards 
the  approximate  length  of  the  period.  In  the  case 
of  the  horse,  the  question  was  less  about  a  new 
formation  than  about  parts  that  lapsed  into  dis- 
use; now  such  parts  are  transmitted  with  in- 
credible tenacity  through  long  periods  of  the  earth's 
history.  It  is  evident  that  more  rapidity  is 
shown  in  transformations  where  adaptation  does 
not  create  entirely  new  organs,  but  merely  modifies 
those  already  existing ;  thus,  for  instance,  where  it 
changes  running  feet  into  climbing  feet,  and  in- 
significant skin-ossifications  into  huge  shields  and 
plates. 


THE  EDENTATA,  OK  ANIMALS  POOR  IN  TEETH.   123 

If,  accordingly,  we  require  a  very  considerable 
length  of  time — one  certainly  extending  back  into 
the  Tertiary — for  bringing  the  Armadillo  and  Gir- 
dled-mouse  back  to  one  family,  we  shall  require  at 
least  as  long  a  period  for  the  development  of  the 
branch  of  Glyptodons  from  the  common  stock. 
Almost  precisely  the  same  latitudes  in  South 
America  where  the  existing  Girdled-animals  find  a 
home,  gave  shelter  during  the  Diluvial  period  to 
the  various  species  of  the  gigantic  Glyptodons. 
Buenos  Ayres  possesses  the  richest  collection  of 
these  very  perfect  fossils.  They  have  been 
admirably  described  by  Professor  Burmeister,1  for- 
merly of  Halle,  who  some  thirty  years  ago  went 
to  reside  in  South  America ;  and  the  descriptions 
could  be  made  as  complete  as  if  he  had  been 
describing  the  skeletons  of  some  common  existing 
animal. 

Glyptodon  clavipes  measures  2-80  m.  from  the 
snout  to  the  end  of  the  tail.  Of  these  1'50  go  to 
the  huge  shield  which  covers  its  back  and  sides, 
forming  one  piece.  The  skull  shows  an  unmis- 
takable resemblance  to  that  of  the  Sloths,  not 
only  as  regards  dentition,  but  also  in  the  pecu- 

1  Burmeister,  Annales  del  Huseo  ptiblico  de  Buenos  Aires. 
1864. 


124 


THE  MAMMALIA. 


liar  formation  of  the  cheek-bone;  however,  as 
regards  the  structure  of  its  limbs  it  keeps  wholly 
within  the  limit  of  the  Armadillo  group.  The 
animal  obtained  its  food  by  burrowing  and  scraping, 
probably  hid  in  caves,  and  protected  itself  from 
the  attacks  of  the  not  very  powerful  Carnivora,  by 
drawing  its  head  under  its  breast  like  the  arma- 
dillo, its  back  being  protected  by  a  shield  similar 

to  that  of  a  gigantic 
tortoise,  its  head  by  a 
helmet  of  bony  plates, 
while  the  bony  rings 
of  its  tail  were  anchy- 
losed,  and  formed  a 
kind  of  tunnel  or 
arched  bridge  of  bone. 
The  Ant-bears  of 
South  America  have 
an  ancestor  in  the 

Glossotherium.  Another  giant  of  Diluvial  South 
America — but  without  any  living  representatives 
— is  Toxodon,  known  to  us  by  its  skull,  which 
measures  0'60  metre;  it  possessed  a  more  com- 
plete dentition,  but  nevertheless  shows  affinity 
to  the  Edentate  type.  Toxodon,  owing  to  its 
isolation,  does  not  account  for  the  existence  of 


FIG.  10.— Head  of  Glyptodon  cla- 
vipes.  One-tenth  natural  size. 
After  Burmeister. 


THE  EDENTATA,   OR  ANIMALS  POOR  IN  TEETH.   125 

any  of  its  contemporaries  or  any  portion  of  the 
living  animals,  and  only  asks  us  to  imagine  round 
about  him,  and  back  to  his  own  day,  a  wealth  of 
forms  that  cannot  be  conceived  in  too  great  a  variety. 

From  the  Tertiary  strata  of  South  America — 
our  knowledge  of  which,  however,  is  very  meagre 
— we  have  no  Edentates.  In  North  America  a  few 
forms,  such  as  the  Moropus  (of  the  size  of  a  tapir) 
have  been  traced  back  to  the  Miocene.  This  fact, 
and  the  frequent  occurrence  in  Nebraska  of  the  re- 
mains of  Giant  Sloths  from  the  transition  period  of 
the  New  Tertiary  to  the  Diluvium,  induces  Marsh 
to  dispute  the  prevailing  idea  that  the  Diluvial 
Edentata  spread  from  the  area  of  their  distribution 
in  the  south,  northwards ;  he  maintains  that  it  is 
more  probable  that  they  migrated  from  the  north, 
southwards. 

Fossil  remains  of  Edentata  have  only  rarely 
been  discovered  in  Europe.  We  have  the  Macro- 
therium  from  the  Middle  Miocene  of  Sansan 
(France)  with  its  peculiar  retractile  claws.  To 
judge  from  the  character  of  its  limbs,  it  might 
have  been  a  climber,  but  can  scarcely  have  been 
this,  for,  as  Gaudry  says,  it  cannot  often  have 
come  across  trees  strong  enough  for  such  exercises. 
The  inexhaustible  beds  of  Pikermi  (Upper  Miocene) 


126  THE  MAMMALIA. 

have  furnished  one  huge  Edentate,  Ancylotherium. 
Finally  a  few  remains  from  the  Upper  Eocene  of 
Quercy  corroborate  what  is  demanded  by  our  theory 
and  common  sense.  "With  this  division  of  the 
living  world,  we  may  be  said,  upon  the  whole, 
to  stand  utterly  helpless  as  regards  geological 
antiquity,  in  so  far  as  the  question  refers  to  a 
special  proof  for  the  origin  of  species,  and  the 
perfectly  justifiable  proof  of  a  general  deduction  is 
not  accepted. 

4.    THE    UNGULATA,    OR   HOOFED   ANIMALS. 

The  usual  classification  of  the  living  mammals 
furnished  with  hoofs  into  many-hoofed,  double- 
hoofed,  and  single-hoofed  animals  appears  as 
natural  and  self-evident  as  convenient.  However, 
it  becomes  utterly  inapplicable  and  proves  alto- 
gether incorrect  when  tested  by  our  present 
scientific  principles,  and  when  we  further  consider 
the  palseontological  material  that  has  gradually 
been  acquired.  Of  no  other  group  have  such 
numerous  fossil  remains  been  found,  and  in  no 
other  have  so  many  lines  been  evolved  from  the 
earliest  Tertiary  periods,  partly  up  to  the  present ; 
hence  the  remark  of  a  recent  writer,  that  '  the 
genus  Horse  is  the  true  "  show  horse  "  of  the  theory 


THE  UNGULATA,  OE  HOOFED  ANIMALS.        127 

of  evolution,'  may  truly  be  applied  to  the  whole 
order.  All  the  animals  of  the  present  age  have  be- 
come what  they  are,  but  in  scarcely  any  other  case 
is  the  process  of  becoming  so  obvious,  or  the  transi- 
tion more  perfect :  the  transition,  that  is,  from  the 
less  specialised  dentition  of  the  Omnivora  to  the 
peculiar  jaw  of  our  horses  and  ruminants,  the 
disappearance  of  the  toes  of  the  five-fingered 
primary-hoofed  animals  down  to  our  two-toed 
ruminants  and  one-toed  horse. 

The  basis  of  the  correct  classification  has  long 
since  been  given  by  Owen,  who  divided  all  the 
Hoofed  animals  into  odd-hoofed  and  pair-hoofed. 
It  is  not  the  number  of  toes  that  is  the  characteris- 
tic feature,  but  the  distribution  of  the  weight  of 
the  body  upon  the  outer  parts  of  the  legs,  or,  what 
is  the  same  thing,  the  relation  of  the  lengthened 
axis  of  the  leg  to  the  middle  toe.  The  Odd-hoofed 
animals  (Perissodactyla)  are  those  with  either  five, 
four,  or  one  toe,  but  where  the  lengthening  of  the 
axis  of  the  upper  and  lower  arm,  and  upper  and 
lower  leg,  passes  through  the  middle  toe,  whereby 
the  middle  toe  has  to  bear  the  main  weight  even 
where  we  have  a  three,  four,  or  five-toed  animal. 
And  Paired-hoofed  animals  (Artiodactyla)  are  those 
where  the  axis  passes  between  the  middle  and  the 


128  THE  MAMMALIA. 

fourth  toe ;  hence  these  two  toes  are  more  active 
than  the  side  toes,  and  have  an  almost  equal 
amount  to  do  in  bearing  the  weight.  They  ac- 
quire strength  by  this  function,  while  the  less  active 
toes  gradually  become  useless  and  finally  disap- 
pear. We  have  already  referred  to  the  importance 
of  the  specialisation  of  the  teeth,  and  to  the  sim- 
plification of  the  limbs  produced  by  the  reduction 
and  disappearance  of  the  toes,  as  an  advance  for 
certain  functions.  And  it  is  self-evident  that  the 
disappearance  of  the  toes  must,  in  a  lesser  or 
greater  degree,  affect  the  middle  part  of  the  hand 
and  foot,  the  roots  of  the  hand  and  foot,  the  bones 
of  the  lower  arm  and  leg,  and  also  the  muscles  and 
other  soft  parts  of  the  limbs. 

Kowalewsky  has  pointed  out  an  exceedingly  in- 
teresting circumstance  connected  with  the  bones  of 
the  hand  and  foot,  and  distinguishes  inadaptive  and 
adaptive  forms  among  the  Hoofed  animals,  where 
the  toes  are  either  partly  rudimentary  or  have 
completely  disappeared.  This  explanation  of  Kow- 
alewsky's  throws  some  light  upon  the  question 
why  so  many  lateral  branches  of  the  Mammalia 
have  died  out,  whereas  previously  we  had  to  be 
satisfied  with  the  general  supposition  that  these 
were  the  very  branches  that  had  not  survived  in 


THE  UNGULATA,   OE  HOOFED  ANIMALS.        129 


the  struggle  for  existence.  The  case  is  this :  the 
original  five-toed  extremity  (compare  above  Fig.  1, 
p.  36)  has,  in  the  second  row  of  tarsals,  one  bone 
for  every  toe.  If  the  side  toes  become  reduced, 
one  of  two  cases  may  then  happen  to  the  bones  of 
the  second  row :  either 
they  become  reduced 
with  the  toe,  or  they 
are  retained  for  the 
remaining  toe ;  i.e. 
they  adapt  themselves 
to  the  circumstances 
of  the  limb  which 
changes  with  the  toes 
and  add  to  its  strength 
and  agility.  The  ex- 
amples adduced  by 
Kowalewsky  are,  in 
fact,  very  instructive. 
In  the  case  of  the 
Eocene  Anoploiherium  (Fig.  11),  the  first  digit  is 
wanting  up  to  the  carpals,  but  the  carpal  bone 
(1)  belonging  to  it  exists,  only  it  is  reduced  and 
is  of  no  further  use.  Of  the  second  digit  the 
shortened  metacarpal  (n)  exists,  as  also  the  carpal 
(2),  but  both  are  useless. 
13 


FIG.  11.— Left  Fore-foot  of  the 
Anoplotherium.  After  Kowa- 
lewsky. 


130 


THE  MAMMALIA. 


Now  if  we  compare  the  same  part  of  the  foot 
of  the  Peccary  (Fig.  12),  the  first  carpal  has 
vanished  with  the  first  toe.  The  second  toe,  of 
which  our  illustration  shows  the  metacarpal  (n), 
is  withdrawn  from  the  ground  as  the  lateral 

toe,  hence  becom- 
ing reduced,  but  its 
carpal  (2)  has  not  be- 
come a  superfluous 
appendage,  as  in  the 
case  of  Anoplothe- 
rium,  it  has  entered 
the  service  of  the 

I  -m\w          T\       tbird»  one  of  the  two 

LI  1  \     \    principal     toes     (in, 

iv) ;  it  has  adapted 
itself  to  the  new  con- 
ditions of  its  organisa- 
tion that  have  gradu- 
ally been  acquired. 

The  illustration 
shows  that  both  animals  are  essentially  the  same 
as  regards  the  fourth  and  fifth  carpals.  In  the 
peccary  the  fifth  toe  is  still  attached  to  the  fifth 
metacarpal,  as  in  the  case  of  the  second  reduced 
toe  of  the  Anoplotherium,  which  has  dwindled 


FIG.    12.— Left  Fore-foot    of    the 
Peccary.    After  Kowalewsky. 


THE  UNGULATA,  OE  HOOFED  ANIMALS.        131 

down  to  a  mere  remnant  of  the  fifth  meta- 
carpal.  But  it  is  of  use  almost  exclusively  to 
the  fourth  toe,  and  has  grown  into  one  piece  with 
its  neighbour,  4.  Kowalewsky  thinks  that  he  may 
safely  affirm  that  the  inadaptive  forms  like  the 
Anoplotherium  had,  as  a  rule,  a  very  short  term 
of  existence,  and  differentiated  within  narrower 
limits  ;  and  that  the  adaptive  forms  possessed  the 
more  advantageous  predisposition  of  being  further 
developed,  as  is  shown  by  their  preservation  and 
transformation  up  to  the  present  time.1 

The  first  incomings  of  the  Hoofed  animals  are 
as  yet  lost  in  the  same  obscurity  as  those  of  the 
other  orders ;  they  are  found  variously  developed 
as  early  as  the  Lowest  Eocene  strata.  A  single 
genus,  indigenous  both  to  the  Old  and  the  New 
World,  possesses  five  toes  on  the  fore  and  hind 
limbs,  but  already  showing  an  inclination  to  odd- 
hoofedism,  if  we  may  use  the  rather  strange  ex- 

1  Filhol  has  uttered  a  decided  protest  against  the  genus 
Anoplotherium.  It  is  said  to  be  plentifully  represented  in  the 
Upper  Eocene  by  a  number  of  sub-genera  and  species.  Filhol 
asks  us  to  consider  that  the  sudden  disappearance  of  the  Ano- 
plotheridffi,  without  leaving  identifiable  descendants,  may  as  well 
be  the  result  of  emigration  as  of  a  general  dying  out.  Still 
Kowalewsky's  opinion  has  the  advantage  of  being  not  merely  a 
supposition,  but  one  based  upon  a  very  plausible  scientific 
deduction. 


132 


THE  MAMMALIA. 


FIG.  13.-  Coryphodcn.     Eight  Fore  and  Hind-foot.    One-sixth 
natural  size.    After  Cope. 


THE  UNGULATA,  OR  HOOFED  ANIMALS.        133 

pression.  The  animal  is  called  Coryphodon,  and  is 
somewhat  the  size  of  a  rhinoceros.  The  toes  are 
all  complete  (Fig.  13) ;  but  i  and  iv  are  strik- 
ingly weaker,  and  in  decidedly  the  strongest, 
corresponding  with  the  lengthening  of  the  axis  of 
the  shank.  The  form  of  the  skull  of  this  earliest 
known  Hoofed  animal  does  not  make  any  strange 
impression,  any  more  than  do  the  limbs.  The 
full  dentition  (forty-four  teeth)  leads  to  the  con- 
clusion of  its  having  lived  upon  different  kinds  of 
food.  But  the  brain — the  circumference  of  which 
can  be  gathered  from  well-preserved  impressions — 
shows  an  inferior  type  of  organisation,  owing  to  its 
insignificant  size  and  the  smallness  and  the  flat  sur- 
face of  the  larger  part  of  the  brain.  It  is,  in  fact,  the 
lowest  and  most  reptile-like  brain  known  to  us.  The 
diameter  of  the  larger  portion  scarcely  exceeds  that 
of  the  spinal  marrow,  the  middle  brain  being  the 
broadest  section.  Further,  the  form  and  position 
of  the  olfactory  lobes  remind  one  of  the  lower 
vertebrates.  The  length  of  the  hemispheres  mea- 
sures one  fifteenth  of  the  skull,  their  volume  one 
twenty-seventh  of  that  of  a  tapir  of  the  same  size. 
Hence  the  brain  of  the  Coryphodon  has  more  the 
appearance  of  that  of  a  lizard  than  of  any  existing 
mammal.  But,  nevertheless,  this  and  similar 


THE  MAMMALIA. 


forms  leave  us  very  far  from  a  proper  knowledge 
of  the  primary  Hoofed  animal.  And  the  connection 
between  Coryphodon  and  the  colossal  Dinocerata 


Fro.  14.— Coryphodon.    Skull  with  Brain.    One-fifth  nat.  size. 
After  Marsh. 

(which  are  confined  to  the  west  of  the  Eocky 
Mountains)  also  appears  very  indefinite.  "We  shall 
again  have  to  return  to  the  Dinocerata. 


THE  UNGULATA,   OK  HOOFED  ANIMALS.         135 

The  palaeontologist,  therefore,  meets  with  Odd- 
hoofed  animals  (Perissodactyla)  as  early  as  in  the 
Lower  Eocene  strata,  and  distinct  from  the  Pair- 
hoofed  animals  (Artiodactyla) .  He  can,  in  both 
groups,  follow  a  few  lines  up  to  the  present,  and 
can  thus  construct  the  pedigrees  of  the  existing 
families,  at  all  events  in  very  probable  outlines. 
In  addition  to  the  above-mentioned  general  form  of 
specialisation — which  received  its  fullest  expression 
in  the  ruminants  and  horses — we  have  a  very 
marked  change  as  regards  the  predominance  and 
the  variations  of  the  group  in  the  New  Tertiary  as 
compared  with  the  Post  Tertiary  periods.  The 
tapir-shaped  and  pig-shaped  Thick-skinned  animals, 
which  at  one  time  swarmed  among  the  moist 
forests  and  marshy  banks,  decrease  in  number, 
while  deer,  antelopes,  and  oxen  become  more  and 
more  the  inhabitants  of  the  newer  formations 
of  forest  lands  and  of  the  grassy  plains — or  at 
least  the  drier  steppe-lands — which  became  possible 
with  the  greater  consistency  of  the  newer  con- 
tinents. Deer,  antelopes,  and  oxen  have,  since  the 
Pliocene  up  to  the  Present,  steadily  and  very 
strikingly  increased  in  number  of  species,  whereas 
the  Odd-hoofed  animals  have  as  steadily  decreased. 
As  late  as  1869  Kutimeyer — in  special  reference 


136  THE  MAMMALIA. 

to  the  Hoofed  animals — was  able  to  maintain,  there- 
fore, that,  'in  spite  of  our  as  yet  knowing  with 
certainty  only  a  very  small  portion  of  the  fossil 
animals,  still  it  has  come  to  seem  at  least  probable 
that  not  only  the  variety  and  very  marked  character 
of  the  forms,  but  that  the  number  of  the  species 
also  has  continuously  increased.'  However,  this 
opinion  requires  modification  since  the  discoveries 
made  in  America  during  the  last  fifteen  years, 
which  discoveries  may,  to  a  certain  extent,  be 
classed  with  FilhoPs  discoveries  in  France.  The 
Hoofed  animals  teach  us  above  all  things,  as  has 
already  been  said,  that  we  live  in  a  world  zoologi- 
cally very  impoverished. 

The  fossil  species  which  have  not  left  any 
living  representative  of  their  former  existence  will 
receive  only  our  second  consideration ;  but  as  this 
very  class  contains  most  of  the  genera  that  must 
be  the  primary  forms  of  the  present  species,  we 
shall  best  attain  our  object  by  showing  the  links 
which  connect  the  mammals  we  have  around  us 
with  those  of  the  primordial  world,  by  starting  in 
a  general  way  from  the  known  Hoofed  animals — as 
a  few  of  the  highest  and  still  blossoming  off- shoots 
of  a  mighty  tree — and  thence  take  a  survey  back 
towards  the  roots. 


THE  UNGULATA,  OK  HOOFED  ANIMALS.        137 

Artiodactyla,  or  Pair-hoofed  Animals. 
The  two  main  groups  of  the  living  Pair-hoofed 
animals  are  the  Pigs  and  the  Euminants.  We  have 
an  approximation  to  the  pigs  (above  all  in  the  form 
of  the  molars)  in  the  hippopotamus,  which  con- 
stitutes a  side  group.  The  characteristic  feature, 
which  is  met  with  even  in  the  earliest  known 
forms,  is  the  peculiar  formation  of  the  crowns  of 
the  molar  teeth ;  and  we  shall  accordingly  desig- 
nate the  Pigs  as  tuberculate-toothed  animals  or 
Bunodonta.;  the  Euminants  as  crescentic-toothed 
animals  or  Selenodonta.  In  animals  of  the  pig 
species  the  enamel  of  the  surface  of  the  crowns 
shows  elevations.  The  almost  four-cornered  crown 
(Fig.  15,  to  the  left)  shows  a  front  and  a  back  wall 
(vt  h),  an  outer  and  inner  side,  an  outer  and  an 
inner  front  tubercle  (AI),  and  an  outer  and  an 
inner  back  tubercle  (ai).  The  tooth  varies  in 
accordance  with  this  scheme.  Elevations  of  the 
enamel  are  met  with  also  in  the  ruminant  type, 
but  present  the  form  of  a  crescent  (Fig.  5,  on  the 
right),  and  much  deeper  folds. 

1.    THE    SUID.E,    OR    PIGS. 

The   Pigs   are   represented   in   Europe  by  the 
widely  distributed  genus  Sus,  and  a  few  others  of 


138 


THE  MAMMALIA. 


lesser  importance,  in  America  simply  by  the 
Peccary,  Dicotyles.  From  Sus  we  can  most  directly 
follow  the  series  in  its  earlier  forms,  whereas  the 
hog-deer  of  Celebes  (Babirussa)  and  the  African  wart- 
hog  (Phacochoerus)  show  peculiarities  of  dentition 
which,  in  the  Babirussa,  have  proceeded  from  new 
and  special  adaptations;  and  the  Phacochoerus 
seems  to  owe  its  existence  to  an  unknown  lateral 
branch. 


FIG.  15. — ^Representation  of  a  Tuberculate  Tooth  and  of  a 
Crescentic  Tooth. 


The  head  of  the  Pig  is  remarkably  long.  Its 
mode  of  life  has  played  a  great  part  in  forming 
this  elongated  shape.  This  is  evident  from  a  com- 
parison of  the  Wild  Boar  with  the  Domestic  Pig,  or 
of  an  animal  kept  in  a  sty  with  an  individual — even 
of  the  same  litter — that  has  had  to  seek  its  food 
in  meadows.  The  more  the  pig  has  to  work  with 
its  head,  by  burrowing,  the  more  it  stretches  the 


//    *  OF  TPK  T    NV 

.    f  UNIVERSITY  J 
THE  STJID^S,  OE  PIGS.  139 

muscles  of  the  neck  attached  to  the  back  of  its 
head,  and  the  more  is  the  plastic  part,  which  is 
specially  soft  in  the  young  animal,  affected  by 
the  mechanical  influence  and  becomes  elongated. 
Further,  the  shape  and  length  of  the  snout  is  the 
result  of  the  pressure  experienced  while  the  pig 
is  obtaining  its  food,  but  is  especially  connected 
with  the  larger  number  and  full  series  of  teeth. 

31          33 

The  dental  formula  l  is:  i  -  c       pm     m—t      The 

31  3      3 

lower  incisors  stand  out  almost  horizontally,  as 
in  the  case  of  some  of  the  plant-eaters,  and  are 
adapted  for  cropping  grasses  in  which  the  tongue 
takes  no  part.  The  canines  of  the  male  animal  de- 
velop into  fearful  weapons,  especially  in  the  case  of 
the  wild  boar.  The  premolars  are  of  an  indefinite 
character  and  of  subordinate  importance,  both  as 
regards  taking  food  and  for  chewing  it.  The 
molars,  on  the  other  hand,  both  in  form  and 
action,  occupy  a  middle  position  between  the  cheek 
teeth  of  the  Carnivora  and  those  of  the  decided 
gr  ass -eater  s ;  yet  in  structure,  in  spite  of  their 
affinity  to  the  latter,  they  show  a  closer  resem- 

1  The  milk-teeth  of  the  Pig  consist  of  four  cheek-teeth.  The 
first  one  is  not  replaced,  but  remains  in  its  position  for  some 
length  of  time,  till  after  the  three  permanent  premolars  have 
appeared. 


140 


THE  MAMMALIA. 


blance  to  those  of  the  Carnivora.  They  are  adapted 
not  only  for  chewing  but 
for  crunching  food.  Their 
dentition  is,  in  fact,  that 
of  an  animal  living  upon  a 
mixed  form  of  food — one  of 
the  Omnivora. 

In  the  structure  of  its 
foot  the  Pig  is  very  closely 
allied  to  the  Peccary,  which 
we  have  already  mentioned 
as  an  example  of  the  so- 
called  adaptive  animal  form. 
However,  the  Peccary  has 
advanced  farther  in  the 
adaptation  of  its  tarsal  hones 
to  the  two  principal  toes 
than  the  Pig,  in  whose  case 
both  the  second  and  the  fifth 
toe  still  almost  wholly  claim 
the  support  of  the  carpals, 
without  thereby  accomplish- 
ing anything  particular  in 
the  way  of  standing  and 
running.  From  the  relation 

between  the  carpals  and  metacarpals  it  is  evident 


FIG.  16.— Eight  Fore-foot 
of  the  Pig. 


THE  SUTD^E,  OR  PIGS.  141 

that  the  Peccary  (Dicotyles),  by  the  simplification  of 
its  limbs — which  is  advantageous  for  running — has 
advanced  farther  than  Sus ;  it  is,  in  fact,  a  better 
runner  than  the  Pig,  and  we  are  fully  justified  in 
supposing  that  both  animals  will  make  still  further 
progress  in  this  direction.  They  are,  without  doubt, 
swifter  runners  than  were  their  ancestors  with  their 
less  reduced  feet,  and  a  further  advantageous  re- 
duction will  depend  only  upon  circumstances.  The 
inward  disposition  towards  this  exists,  but  I  must 
beg  the  reader  not  to  confound  the  simple  word  '  dis- 
position' with  the  dangerous  word  'tendency,'  the 
play-word  of  philosophers  and  one  apt  to  lead  over 
to  the  idea  of  purpose.  If,  after  many  thousands 
of  years,  the  foot  of  the  American  Peccary  and  the 
European  Sus  should  have  lost  every  vestige  of  its 
second  and  fifth  toes,  this  would  be  a  perfectly  in- 
telligible, nay,  a  most  obvious  case  of  homceogenetic 
convergence.  If,  however,  our  Pig  and  Peccary 
should  no  longer  exist  for  the  zoologists  of  the 
future,  they  would  most  probably  regard  the  anti- 
cipated and  distinctly  two-toed  feet  of  both  animals 
as  having  been  inherited. 

This  consideration  may  now  lead  us  to  the  ques- 
tion as  to  the  primary  forms  of  our  living  Suidce. 

The  genus  Sus  is  found  only  in  the  Old  World,  even 
14 


142  THE  MAMMALIA. 

as  fossils,  and  extends  back  as  far  as  into  the 
Middle  Miocene.  A  powerful  Boar  is  one  of  the 
numerous  fauna  found  in  Pikermi.  Its  discoverer, 
Gaudry,  has  given  it  the  name  of  S.  Erymanthius. 
The  line  is  continued  through  the  strata  of  the 
Eocene  by  the  genus  Palceochoerus  and  Ckoerotherium, 
still  with,  or  rather  already  with,  a  dentition  of  the 
Pig  species,  but  still  with  less  reduced,  or,  more 
correctly  speaking,  still  with  a  full  number  of  toes. 
Even  Palceochcerus  typus  from  the  Lower  Miocene  of 
southern  France  shows  the  characteristic  teeth  of 
the  genus  Pig  (Fig.  17) :  on  either  side  three  incisors, 
a  good-sized  canine  (c),  four  premolars  and  three 
molars.  A  still  earlier  form  of  the  tuber culate- 
toothed  animal  is  Choer other ium,  which  still  has  four 
toes  almost  equally  developed.  The  *  ancestral  line ' 
of  Primeval  Pigs  is  thus  evident  enough  for  those 
who  choose  to  follow  it,  and  is  more  distinct  than 
many  a  human  pedigree. 

Among  the  cousins  of  this  family  who  could  not 
maintain  an  existence,  and  whose  position  is,  in  fact, 
somewhat  doubtful,  are  Chceropotamus,  and  also  the 
colossal  animal  Anthracotherium,  from  the  Coal  for- 
mation, which  attained  the  size  of  a  rhinoceros. 

America  likewise  possessed  a  line  of  pig-shaped 
animals  which  may  be  traced  from  the  Eocene  up 


THE  SUIDJE,  OR  PIGS.  143 

to  the  present  living  Peccary,  and,  with  the  exception 
of  a  few  species,  is  one  different  from  that  of  the 
primordial  world.  In  this  series  we  find  repeated 
the  transformations  and  reductions  which  we  have 
just  followed.  Marsh  makes  out  the  line  from 
the  Eocene  thus :  Eohyus,  Helohyus,  Perchcerus, 
Tinohyus,  Dicotyles.  Hence  we  still  stand  before 
the  unanswered  questions,  whether,  to  what  extent, 


FIG.  17. — Palseochoerus  typus,  Left  Upper  Jaw.     Nat.  size. 
After  Gaudry. 

and  in  which  direction  (from  Europe  westwards? 
from  Asia  ?  or  from  America  ?)  the  exchange  took 
place,  as  affecting  the  formation  of  the  differences 
of  the  species  ?  or  whether  the  development  was  a 
parallel  one ;  Choeropotamus  to  the  Pig,  Eohyus  to  the 
Peccary?  Geologists  are  pretty  well  agreed  that 
during  the  Earlier  Tertiary  period,  up  to  the  Lower 
Miocene,  the  Old  and  New  World  were  connected  by 


144  THE  MAMMALIA. 

land,  and  during  the  Later  Tertiary  as  well.  An 
exchange,  therefore,  may  have  taken  place,  and 
certainly  must  have  taken  place  up  to  the  Eocene 
period,  as  is  proved  by  the  occurrence  of  Coryphodon 
in  Europe  and  America,  and  of  Palaeotherium  and 
Anoplotherium  in  Europe  and  South  America.  But 
for  a  long  period,  during  the  Miocene,  there  was  no 
connection  either  between  North  and  South  America 
or  between  America  and  the  Old  World.  Hence 
during  this  period  there  must,  in  any  case,  have 
been  a  further  parallel  development  upon  the  same 
basis,  a  parallel  development  of  Pair-hoofed  animals 
with  tuberculate  teeth,  where  the  reduction  of  the 
toes,  discussed  above,  was  an  advantage;  and  the 
supposition  of  an  even  wider  case  of  convergence  is 
perfectly  admissible  from  a  scientific  point  of  view. 

2.    THE    HIPPOPOTAMUS,    OR   RIVER-HORSE. 

The  Hippopotamus  has  to  be  traced  back  to  a 
similar  primary  form,  for  it  is  the  only  living 
representative  of  the  Hoofed  animals  with  tuber- 
culate teeth  which  has  preserved  the  old  structure 
of  the  limbs  pretty  well  unchanged.  The  still 
uncut,  rootless  cheek-tooth  (Fig.  18)  somewhat 
resembles  a  double  mitre  with  a  basal  setting,  which 
in  front  and  at  the  back  passes  over  into  a  three- 


THE  HIPPOPOTAMUS.  145 

sided  shield,  and  has  a  wart-shaped  protuberance 
between  the  two  halves  both  out  and  inside.  Each 
half  consists  of  two  almost  three-sided  tubercles, 
which  lie  flat  against  the  inner  sides  that  are 
turned  towards  one  another.  From  this  it  is 
evident  that  the  enamel  outline  of  the  used  tooth 


FIG.  18. — Second  Lower  Molar  of  the  Eiver-horse,  to  the  right. 
Nat.  size. 

(Fig.  19)  consists  originally  of  two  pairs,  with  the 
basal  line  of  the  three  corners  turned  towards  one 
another,  and  which  do  not  coalesce  till  they  have 
been  used  for  a  long  time. 

The    Hippopotamus    has    become    almost    an 
amphibian   in   its   mode   of    life;    its    skull    and 


146 


THE  MAMMALIA. 


dentition  show  very  little  modification,  and  the 
formation  of  its  foot  has  remained  very  faithful  to 
the  primary  type  from  the  Eocene,  the  lineal 
descendants  of  which,  unfortunately,  cannot  be 
pointed  out  singly.  The  Eocene  animals  with 
tuberculate  teeth,  and  likewise  the  Early  Tertiary 
ancestors  of  the  Euminants,  had  to  dwell  prin- 


FIG.  19. — First  Upper  Molar  of  the  Hippopotamus,  to  the  right. 
But  little  worn  off. 

cipally  in  waters  and  on  marshy  ground.  Their 
descendants  adapted  themselves  gradually  to  life 
on  dry  ground,  and  this  is  connected  with  the 
advantageous  reduction  of  the  toes.  The  Hippopo- 
tamus family  has  taken  an  opposite  course,  from 
being  an  animal  that  liked  the  marshy  soil  of 
the  primeval  forests,  it  has  become  almost  an 


THE  HIPPOPOTAMUS. 


147 


aquatic  creature,  and  accordingly  has  preserved 
the  completeness  of  hand  and  foot,  the  four  toes 
almost  fully  developed.  In  Fig.  20  we  have  the 
root  and  middle  portion  of  the  right  fore-foot,  and 
we  will  here  use  the  terms  generally  given  to  this 
part  of  the  skeleton  in  Man  and  the  higher 


FIG.  20. — Hippopotamus,  Eight  Fore-foot.    After  Kowalewsky. 

vertebrates  :  s  (scaphoideum)  =  radiale  ;  I  (lunatum) 
=  intermedium ;  p  (pyramidale)  =  ulnare ;  t  (trape- 
zoideum)  =  carpale  2 ;  m  (magnum  or  capitatum)  = 
carpale  3 ;  u  (uncinatum)  =  carpalia  4  +  5. 

A  one-toed  hippopotamus  in  the  natural  course 
of  development  is  an  impossibility.  The  gradual 
reduction  of  the  toes,  as  already  said,  can  be  con- 


148  THE  MAMMALIA 

nected  only  with  the  drying  up  of  marshy  lands. 
And  if,  by  some  extravagant  flight  of  the  imagina- 
tion, we  could  conceive  the  existence  of  a  one-toed 
leviathan,  the  very  fact  of  its  possessing  a  one-toed 
foot  would  be  the  cause  of  its  speedy  extinction. 
As  regards  dentition  also  the  hippopotamus  shows 
signs  of  being  geologically  very  old.  The  skull  of 
the  unwieldy  creature  reminds  one  of  a  clumsily- 
formed  box.  The  breadth  and  height  of  the  muzzle 
are  produced  by  the  enormous  development  of  the 
middle  incisors  and  of  the  canines.  All  of  these 
teeth  are  furnished  with  roots  that  are  not  closed, 
but  open  wide  apart.  It  is  certainly  not  impossible 
that  these  teeth  assumed  this  form  first  among  the 
nearer  ancestors  of  the  river-horse.  But  it  is  more 
probable  still  that  the  disposition  to  assume  this 
form  was  a  remote  inheritance,  and  that  it  was 
only  by  accommodating  itself  to  feed  on  aquatic 
plants  that,  as  regards  position  and  size,  the  teeth 
have  grown  into  such  ugly  but  useful  tusks. 

It  has  been  already  stated  that  the  river-horse 
is  the  only  representative  of  its  family.  This 
remark  requires  some  explanation;  for  we  have 
not  only  the  well-known  and  so-called  Nile-horse, 
which  is  distributed  over  a  large  portion  of  central 
Africa,  but  there  is  a  second  species,  only  5  feet 


THE  HIPPOPOTAMUS.  149 

in  length,  which,  among  other  things,  is  distin- 
guished by  the  remarkable  shortness  of  the  face  as 
compared  with  the  total  length  of  the  skull.  This 
animal,  which  is  met  with  in  Siberia,  has  been 
classed  apart  from  the  hippopotamus  as  a  distinct 
species  under  the  name  of  Choeropsis.  As,  more- 
over, the  dentition  is  not  quite  the  same,  this 
separation  may  be  allowed  to  pass;  but  both 
species  are  and  remain  '  river-horses/  and  all  that 
has  been  said  above  applies  to  the  smaller  species 
as  well. 

It  is  only  quite  recently  that  we  have  become 
more  intimately  acquainted  with  a  third  species,1 
the  Hippopotamus  madagascariensis,  which,  as  re- 
gards size — it  became  some  7  feet  long  while  the 
Nile  horse  attains  11  feet — fills  the  gap  between 
the  two  African  species,  and  as  regards  skull  and 
dentition  approaches  very  close  to  the  Hippopot- 
amus amphibius.  Its  occurrence  is  extremely  in- 
teresting, inasmuch  as  it  leads  from  Africa  over  to 
Madagascar,  where  its  remains  were  found  in 
marshy  deposits  together  with  those  of  the  colossal 
bird  ^Epyornis.  Its  having  been  found  in  company 


1  Goldberg,  '  Undersogelser  over  en  subfossil  flodhest  fra 
Madagascar,'  Christiania  Videnskabs  selskabs  Forhandlingar, 
1883,  No.  6. 


150  THE  MAMMALIA. 

with  this  bird,  and  the  nature  of  the  locality  where 
it  was  discovered,  justify  the  expression  of  '  sub- 
fossil  '  which  is  given  to  the  species.  It  lived  on 
the  threshold  between  the  Diluvium  and  the  Pre- 
sent. And  even  granting  that  Madagascar  and 
Africa  were  at  one  time  connected  by  land,  their 
separation  must,  nevertheless,  have  taken  place 
early  in  the  Tertiary,  and  accordingly  the  stability 
of  the  genus  Hippopotamus  is  also  proved  from  a 
geological  point  of  view.  It  is  not  only  the  form- 
ation of  the  foot  that  points  to  very  ancient  pri- 
mary forms  to  be  looked  for  beyond  the  Tertiary 
period ;  but  the  dentition  also — which  had  special- 
ised even  before  the  separation  of  the  family  into 
the  African  and  the  Madagascar  species — has  varied 
only  to  a  very  small  extent. 

8.   THE   RUMINANTIA,   OR   CUD-CHEWING  ANIMALS. 

After  setting  aside  the,  at  present,  very  subor- 
dinate group  of  pig-shaped  Pair-hoofed  animals, 
and  the  Hippopotamus,  all  the  remaining  forms 
of  this  division  belong  to  the  Euminants.  As  all 
are,  for  the  most  part,  lively  and  nimble  animals, 
they  do  not,  while  grazing,  take  proper  time  to 
masticate  their  food  sufficiently,  but  hurriedly  stuff 
their  paunch  full  of  provision  and  then  retire  to 


THE  EUMINANTS.  151 

some  safe  retreat,  where  they  assist  the  digestive 
process  by  giving  the  grasses  and  leaves  consumed 
a  subsequent  crunching  and  chewing.  The  Eumin- 
ants  do  not  bite  off  the  plants,  but  tear  them  off, 
in  doing  which  the  tongue  plays  an  important  part 
as  an  organ  for  grasping,  especially  when  long 
grasses  and  branches  have  to  be  dealt  with.  In 
this  mere  tearing  off  of  grasses,  &c.,  the  incisors  of 
the  upper  jaw  can  be  dispensed  with ;  it  may  be 
said  that  with  the  development  of  meadow  plants 
and  pastures,  these  teeth  have  in  course  of  time 
become  superfluous.  Only  animals  of  the  Camel 
species  show  rudiments  of  the  upper  incisors,  and 
in  addition  to  this  case,  canines  have  been  pre- 
served by  the  musk-deer.  The  crowns  of  the  molars, 
as  a  rule,  show  two  transverse  ridges,  and,  moreover, 
the  upper  and  lower  molars  fit  in  such  a  manner 
that  they  can  glide  over  one  another  from  right  to 
left  and  also  in  a  horizontal  manner,  as  may  be 
seen  in  any  ox  or  sheep  '  chewing  the  cud.'  This 
movement  of  chewing  is  rendered  possible  by  the 
condyle  of  the  lower  jaw  not  being  sunk  into  a 
transverse  socket  of  the  temporal  bone,  as  in  the 
case  of  the  Carnivora,  or  into  a  furrow  running 
parallel  with  the  axis  of  the  skull  so  as  to  move 
backwards  and  forwards,  as  in  the  Kodents,  but  by 


152  THE  MAMMALIA. 

being  allowed  free  play  upon  an  almost  level,  or 
even  a  somewhat  raised  surface. 

All  Ruminants  possess  the  above-mentioned 
typical  molars  with  the  enamel  crescents  running 
in  the  direction  of  the  longitudinal  axis  of  the 
skull,  which,  of  course,  present  a  very  different  ap- 
pearance—within the  boundaries  of  the  generic 
characteristics — according  to  age  and  wear.  Fig. 
21  shows  an,  as  yet,  uncut  fourth  right  molar  of 
a  calf  as  seen  from  the  front  and  the  inner  side. 
It  seems  to  consist  of  two  almost  quadrilateral 
prisms,  both  terminating  on  the  outer  and  inner 
side,  in  two  curved  flaps  (A-I  and  a-i).  All  the 
surfaces,  which  pass  over  into  various  curves  and 
folds,  one  within  the  other,  and  are  lost  in  the  interior 
of  the  tooth,  consist  of  the,  as  yet,  imperfect  and 
still  somewhat  soft  layer  of  enamel.  Below  it  is 
the  dentine,  which  is  likewise  just  beginning  to 
develop,  and  round  about  in  the  depressions,  between 
A  and  i  and  a-i,  we  find  the  incomings  of  the 
cement  which  is  still  a  membraneous  formation. 
Now,  if  we  take  this  embryo  tooth  and  compare 
it  with  the  polished  edge  of  one  of  the  already  cut 
front  teeth  (Fig.  21,  n),  we  shall  at  once  obtain  a 
clear  idea  of  the  relation  of  the  enamel  folds  and 
edges  of  the  molar  of  a  full-grown  animal.  The 


THE  RUMINANTS. 


153 


transverse  ridges,  which  fit  into  the  depressions  or 
transverse  valleys  of  the  opposite  row  of  teeth, 
remain  throughout  life,  even  though,  at  a  later  age, 
they  may  become  more  and  more  rubbed  off  and 
level.  The  crescents,  which  become  filled  with 
cement  and  are  encased  on  the  outside  by  enamel, 
on  the  inside  by  dentine  (tooth-bone),  A,  i,  a,  i,  are 


FIQ.  21. 

L  Right  upper  molar  of  a  calf  before  it  has  cut  the  gums ;  <,  inner  side ; 

A,  a,  the  outer  lobes  of  enamel ;  /,  i,  the  inner  lobes. 
IL  The  right  molar  of  a  calf  that  has  cut  the  gums,  artificially  ground ;  from 

behind  and  the  outer  side. 


the  transverse  sections  of  the  flaps  of  the  same 
name ;  B  and  6  are  the  arched-shaped  spaces  which 
likewise  become  filled  with  cement,  and  were  ob- 
viously larger  in  the  thin-walled,  uncut  tooth.  If 
we  weigh  the  different  possibilities  of  the  folds  of 
the  outer  walls,  the  form  of  the  crescent,  the  develop- 
ment of  the  side  folds  and  pillar-shaped  processes, 
15 


154  THE  MAMMALIA. 

we  come  to  understand  the  great  variety  which  dis- 
tinguishes the  Selenodonts  among  one  another,  and 
which  becomes  all  the  more  marked,  the  more  ob- 
stinately the  characteristic  form  is  preserved. 

But  since  Kowalewsky's  classic  works  there  can 
be  no  question  that  the  peculiarities,  connected  with 
the  reduction  of  the  limbs,  are  testimonies  at  least 
as  distinctive  and  trustworthy  for  the  Present  and 
the  Past. 

The  majority  of  the  living  Buminants  are  divided 
into  the  large  families  of  the  Deer,  the  Antelopes, 
and  the  Oxen.  The  last  two,  as  horned  animals, 
are  more  closely  allied  to  one  another  than  to  the 
deer.  The  goats  and  sheep  are  closely  allied  to 
the  antelopes.  Apart  from  all  these  we  have  the 
Camels,  to  which  we  shall  first  direct  our  attention, 
for,  at  least  as  regards  dentition,  they  have  pre- 
served a  higher  geological  antiquity  than  the  others. 

4.   THE   CAMELIDJE,    OE   CAMELS. 

When  Kiitimeyer  calls  the  llama  '  a  late  offshoot 
of  the  Eocene  Anoplotheriae,  and  as  originating  first 
in  America,'  he  gives  a  proof  of  the  utter  uncer- 
tainty which  prevailed  about  ten  years  ago  as  to 
the  position  and  historical  development  of  the  two 
species  which,  since  Buffon's  day,  had  been  regarded 


THE  CAMELS.  155 

as  belonging  to  one  another.  Of  the  two  species  of 
camels  the  one  with  two  humps  is  assigned  to  Cen- 
tral Asia;  the  other  has  been  distributed  over  a 
large  portion  of  Africa  by  Asiatic  nomads,  and 
represents  a  peculiar  mode  of  life.  The  llama 
'vicariates'  for  them.  The  hoofs  are  small,  but 
the  foot  has  a  broad  horny  sole ;  the  skeleton  of 
the  foot  is  that  of  a  true  Euminant.  The  camels 
differ  from  all  the  living  Kuminants  by  the  total 
absence  of  horns  and  by  a  fuller  dentition ;  for 
they  not  only  possess  strong  sharp  canines,  but  an 
incisor  in  the  mid  jaw-bone,  somewhat  to  the  side. 
All  the  other  Kuminants,  without  exception,  have 
lost  their  upper  incisors.  On  this  account,  and 
because  of  the  superficial  resemblance  in  the  form 
of  the  skull  with  that  of  the  horse,  camels  were 
formerly  classed  as  a  group  standing  midway  be- 
tween the  horses  and  the  two-hoofed  animals ;  this, 
however,  is  an  unwarrantable  conjecture.  American 
investigators  have,  on  the  other  hand,  now  made 
us  acquainted  with  a  whole  series  of  primeval 
forms,  according  to  which  the  camel  appears  to  be 
a  very  old  branch  of  the  Selenodonts. 

Marsh  gives  us  the  result  of  his  own  and  of 
Leidy's  observations  thus :  '  A  most  interesting 
line,  that  leading  to  the  camels  and  llamas,  sepa- 


156  THE  MAMMALIA. 

rates  from  the  primitive  selenodont  branch  in  the 
Eocene  probably  through  the  genus  Parameryx.  In 
the  Miocene,  we  find  in  Pcebrotherium  and  some 
nearly  allied  forms,  unmistakable  indications  that 
the  cameloid  type  of  Euminant  had  already  become 
partially  specialised,  although  there  is  a  complete 
series  of  incisor  teeth,  and  the  metapodial  bones 
are  distinct.  In  the  Pliocene  the  camel  tribe  (in 
America)  was,  next  to  the  horses,  the  most  abun- 
dant of  the  larger  mammals.  The  line  is  continued 
through  the  genus  Procamelus,  and  perhaps  others, 
and  in  this  formation  the  incisors  first  begin  to 
diminish  and  the  metapodials  to  unite.  In  Post- 
Tertiary  we  have  a  true  Auchenia  represented  by 
several  species,  and  others  in  South  America,  where 
the  alpacas  and  llamas  still  survive.  From  the 
Eocene  almost  to  the  present  time  North  America 
has  been  the  home  of  vast  numbers  of  the  Camelidae, 
and  there  can  be  little  doubt  that  they  originated 
there  and  migrated  to  the  Old  World.'  * 

1  Cope,  in  1877,  gave  a  fuller  account  of  these  opinions.  The 
Miocene  Pcebrotherium  possesses  of  grinders  p.  4,  m.  3.  The  two 
elongated  metapodials  have  not  coalesced  ;  seven  tarsals.  Then 
conies  Protolabos  still  with  p.  4,  w.  3 ;  the  last  molar  is  more 
prismatic.  The  incisors  also  are  still  there  in  full  number,  but 
fall  out  readily.  Procamelus  is  the  first  to  show  incisors  like 
our  present  camel,  yet  still  p.  4,  m.  3.  The  side  rudiments 
of  the  metatarsals  of  P&brotherium  have  disappeared,  hence  the 


THE  CAMELS.  157 

Nothing  can  well  be  said  in  opposition  to  this. 
Our  illustration  below  (Fig.  22),  gives  the  upper 


FIG.  22.— Auchenia  hesterna.    Second  Molar  of  the  Left  Upper 
Jaw.    Nat.  size  (after  Leidy). 

molar  of  one  of  those  Diluvial  llamas,  the  Auchenia 
hesterna,  in  the  natural  size. 

trapezoid.     The  metatarsals  have    coalesced    and  become  the 

A   n q 

*  canon-bone.'    Then  conies  Pliauchenia  with  — : cheek-teeth, 

o   — 3 

q  q  A  O 

Camelus,    ]     -   ,  Auchenia  - — —.      A  more    and  more    con- 
2  —  o  1  —  o 

tinuous  delay  in  the  formation  of  the  teeth  is  observed ;  the 
teeth  eventually  no  longer  cut  the  gum,  and  finally  disappear 
completely,  a  process  which  is  repeated  in  many  other  lines. 
The  occurrence  of  the  llama  in  South  America  shows  that  the 
causes  which  led  to  its  extinction  in  North  America  did  not 
exist  in  the  southern  continent. 


158  THE  MAMMALIA. 

5.   THE   CERVID.E. — DEER  AND   THEIR  KINDRED   FORMS. 

Riitimeyer,  in  his  '  Natural  History  of  the  Deer,' 
when  speaking  of  the  characteristic  features  that 
distinguish  the  various  forms  of  deer,  maintains 
that  the  antlers  are  periodical,  and  that  they  are 
attributes  confined  to  the  males  of  the  species. 
In  looking  for  the  relationship  between  the  forms — 
principally  in  the  female  skull,  as  in  the  case  of  the 
Euminants — he  finds  the  character  of  the  deer  (as 
compared  with  the  antelopes  and  oxen)  to  consist 
in  the  very  elongated,  almost  cylindrical  shape  of 
the  skull.  This  is  caused  by  the  great  length  of 
the  olfactory  tube  with  a  lesser  height  of  the  toothed 
portion  of  the  upper  jaw.  The  skull  is  elongated 
and,  as  compared  with  the  facial  part,  is  less 
voluminous  than  in  the  case  of  the  horned  animals ; 
the  brow  is  less  of  an  abrupt  incline,  the  axis  of  the 
skull  straight.  The  character  of  the  head  of  the  deer 
may,  of  course,  be  thus  described,  and  Kutimeyer 
has  endeavoured  also  to  characterise  the  antelopes 
and  oxen.  Still,  it  cannot  be  denied  that  the 
antlers,  nevertheless,  play  a  very  great  part,  and 
that  their  existence  is  of  decided  importance  in 
the  classification  of  the  deer. 

The  common  Koe  and  Eed  Deer  furnish  us  with 


THE  CEBVID.E,   OR  DEER.  159 

examples  of  very  different  degrees  of  develop- 
ment in  the  antlers  of  single  species;  and  by 
observing  the  annual  changes  of  the  antlers  we  can, 
with  almost  certainty,  trace  the  different  stages 
attained  by  the  various  species  with  less  fully 
developed  antlers.  The  first  sign  of  the  coming  of 
th3  antlers  in  the  calf,  is  a  thickening  and  pro- 
truding of  the  frontal  bone,  the  incomings  of  the 
permanent  base  of  the  horn.  Between  it  and 
the  upper  layer  of  skin  are  then  formed  the 
beginnings  of  the  actual  antlers — ossifications  of 
the  skin — which  soon  coalesce  with  the  frontal 
process,  dry  up  after  completing  their  growth,  and 
fall  off  after  pairing  time.  The  antlers  of  the  first 
year — the  stem  or  beam — consist  of  a  pair  of  simple 
stumps  with  the  circular  ridge  of  bone  called  the 
burr.  The  following  years  furnish  the  branches  or 
tynes. 

This  development  of  the  antlers  in  the  indivi- 
dual case  of  the  red  deer,  Kutimeyer  compares  with 
the  antlers  in  the  historical  and  geological  succes- 
sion of  stag-shaped  animals,  which  in  the  Lower 
Miocene  are  still  without  antlers.  In  the  Middle 
Miocene  of  Sansan  and  Giinzburg,  and  in  the 
Upper  Miocene  of  Eppelsheim,  we  first  meet  with 
an  animal  that  is  almost,  but  still  not  completely, 


160 


THE  MAMMALIA. 


a  stag. 


Frontal  protuberances  very  elongated, 
beams  with  single  branches  are 
there,  but  no  burr  (Fig.  23). 
The  genus  has  been  described 
under  various  names,  as  Dicro- 
cerus,  Prox,  Procervulus.  The 
tynes  are  often  found  broken  off, 
and  it  cannot  be  said  with  cer- 
tainty where  accident  ends,  and 
the  regular  periodical  casting  off 
has  begun.  It  would  seem  as  if 
the  casting  had  become  estab- 
lished from  the  irregular  occur- 
rence— partly  the  drying  up  of 
the  skin  and  the  brittleness  con- 
nected with  this. 

Rutimeyer  observes  that  it 
is  difficult  to  distinguish  the 
primary  stags  from  the  primary 
antelopes,  and  that  perhaps  the 
North  American  prong-horned 
antelope  which,  curiously  enough, 
casts  its  horns  annually,  must  be 
traced  back  to  those  indefinite 
primary  forms.  Cope  had  made 
the  same  observation  in  1877  when  he  wrote  :  *  The 


i 


FIG.  23.— Prox  fur- 
catus.  Left  antler. 
One-half  nat.  size. 


TUB  CERVID^,   OR  DEER.  161 

genus  Antilocapra  is  related  to  the  Dicrocerus  by 
its  pronged  horns  and  the  hairy  covering  of  skin 
which  constitutes  the  immature  stage  of  the  horn- 
sheath.'  The  Procervulus  mentioned  ahove  was  a 
widely  distributed  genus  in  the  Miocene  period,  as 
is  proved  by  the  discoveries  in  New  Mexico  and 
Nebraska.  The  genus  Cervulus,  which  is  dis- 
tributed over  both  the  Old  and  the  New  World  in 
about  eleven  different  species,  must  be  regarded  as 
a  diluvial  remnant  of  the  genus  Procervulus,  by 
the  side  of  the  more  modern  family  of  the  Deer, 
which  show  a  further  advance  in  the  development 
of  their  antlers.  The  best  known  representative  of 
the  genus  is  the  Muntjak  (Cervulus  muntjac)  in 
India  and  the  Sunda  Islands. 

In  the  Deer,  as  in  the  case  of  most  of  the  living 
pair-toed  animals,  the  two  metatarsals  which  sup- 
port the  two  fully  developed  toes  have  coalesced 
into  the  so-called  cannon-bone.  Their  limit  is 
indicated  by  a  more  or  less  distinct  longitudinal 
furrow  on  the  front  side,  frequently  also  by  a 
deeper  indentation  in  the  lower  joint.  We  never 
meet  with  complete  metatarsal  bones  for  the  two 
outer  toes  that  are  removed  from  the  ground.  The 
modifications  which  prevail  in  this  respect,  within 
the  group,  appear  of  very  little  importance  and 


162 


THE  MAMMALIA. 


interest  when  considered  by  themselves,  but  when 
taken  in  connection  with  the  geographical  distribu- 
tion of  the  animals,  are  of  great  significance.  As 


FIG.  24. 

A.  .Left  fore-foot  of  the  Red  Deer.  S.  Left  fore-foot  of  the  common  Roe. 
<?,  Cannon-bone ;  m,  metacarpals ;  p,  upper  phalange.  (7.  Second  row  of 
tarsal  and  metatarsal  bones  of  the  Gelocus.  After  Kowalewsky. 

examples  of  this  we  may  take  the  red  deer  and  the 
common  roe  (Fig.  24).  The  rudimentary  toes  in 
both  cases  consist  of  three  phalanges.  In  the  red 


THE  CERVIDJE,  OR  DEER.  163 

deer  the  first  of  these  is  smaller  than  the  other 
two,  whereas  in  the  roe  the  first  one  is  of  the  pro- 
portionate size.  Now  this  arises  from  the  fact  that 
the  rudimentary  digits  of  the  deer  have  become 
entirely  detached  from  the  metacarpals,  and  that 
only  the  rudimentary  upper  end  of  it  remains 
(A,  m).  The  roe  still  possesses  the  lower  portion 
of  this  bone  (B,  m)  and,  moreover,  in  connection 
with  the  first  phalange.  The  red  deer  is  a  '  plesio- 
metacarpal '  cervide,  the  common  roe  a  '  tele-meta- 
carpal '  cervide.  All  the  thirty-nine  known  species 
of  Cervidae,  confined  to  the  Old  World,  are  con- 
stituted like  the  deer  with  the  exception  of  the  two 
species  of  roe  and  the  hornless  Hydropotes  in 
China,  with  which  we  have  only  recently  become 
more  intimately  acquainted.  These  three  latter 
species,  however,  as  regards  the  construction  of 
foot,  are  allied  to  the  American  deer.  Of  the 
twenty  American  species  with  tele-metacarpals,  one, 
however,  the  Wapiti  (Cervus  canadensis),  is  not 
related  to  the  others,  but  to  the  Europe- Asia  tic 
group. 

From  the  formation  of  the  foot,  therefore,  we 
find  an  almost  perfect  means  for  distinguishing  the 
specise.  And  this  leads  to  the  very  natural  supposi- 
tion that  the  American  deer  developed  in  the  New 


164  THE  MAMMALIA. 

World,  and  the  Europe- Asiatic  species  in  the  Old. 
It  is  only  the  ancestors  of  the  Eoe  and  the  Hydro- 
potes  that  must  not  be  looked  for  in  the  Old  World ; 
they  are  scattered  members  of  the  group  from  the 
other  side  of  the  ocean,  like  the  Canadian  species 
which,  in  the  days  when  the  two  continents  were 
connected  by  land,  separated  entirely  from  their 
Europe- Asiatic  cousins.  It  is  found  in  the  Qua- 
ternary strata  of  Europe,  e.g.  in  those  of  Louverne, 
near  Le  Mans,  where  it  lived  as  a  separate  family 
by  the  side  of  the  red  deer,  but  soon  afterwards, 
for  some  unknown  causes,  vanished  from  this 
locality  and  reappeared  in  the  New  World. 

The  reduction  of  the  side  toes  and  the  dis- 
appearance of  the  one  or  the  other  ends  of  the 
metacarpals  took  place  after  the  still  four-toed  and 
geologically  older  stag-shaped  animals  had  acquired 
antlers.  This  may  have  been  the  course  taken 
by  their  development,  unless  we  are  to  assume 
that  the  antlers  appeared  in  different  localities  as 
a  parallel  formation,  yet  not  till  after  the  separation 
of  the  older  hornless  Euminants,  which  likewise 
showed  a  reduction  of  the  limbs  spoken  of  above. 
The  latter  case  is  very  probable,  and  must  be 
drawn  into  the  circle  of  combinations,  for  in  Gelocus 
we  have  become  acquainted  with  a  very  ancient 


THE   CERVID^E,   OK  DEER.  165 

Kuminant  of  this  kind,  out  of  which  both  plesio- 
metacarpals  as  well  as  tele-metacarpals  forms  might 
have  developed.  Gelocus  is  an  adaptive  species  of 
Ruminant  from  the  Eocene.  The  skull  as  yet 
scarcely  shows  the  character  of  the  ruminant,  but 
the  molars  are  already  reduced  to  f- ,  whereas  other 
genera  of  the  same  age  show  -f.  The  two  principal 
metatarsals  (Fig.  24,  c,  in,  iv)  have  coalesced 
along  almost  their  entire  length ;  the  metatarsals 
of  the  side  toes  have,  however,  disappeared  in  the 
centre  (Fig.  24,  n,  v),  and  only  the  lower  and 
upper  ends  remain  (ra).  Animals  of  this  kind 
might  have  descendants  with  feet  of  the  Deer 
species,  another  with  feet  like  the  Eoe.  At  all 
events,  deer  and  roe,  both  of  these  well-known 
denizens  of  our  forests,  have  been  strangers  to  one 
another  from  very  remote  times,  strangers  as 
complete  as  the  Canadian  stag  (the  Wapiti)  is  to 
all  the  other  American  Cervidae. 

An  intermediate  position  between  them  is  occu- 
pied by  the  Elk  and  Reindeer.  Both  are  circumpolar 
species,  and  both,  as  regards  construction  of  the 
foot — as  tele-metacarpal  species — are  allied  to  the 
deer  of  the  New  World,  the  reindeer,  moreover,  by 
the  form  of  the  nasal  cavity.  Our  material  is  at 

present  too  fragmentary  to   enable   us  clearly  to 
16 


166  THE  MAMMALIA. 

survey  both  sides.  But  all  of  these  observations, 
which  we  owe  principally  to  Sir  Victor  Brooke,1 
confirm  Kiitimeyer's  remark  that  the  form  and 
development  of  the  antlers  can  only  very  cautiously 
be  made  use  of  as  a  means  for  a  strict  classification 
of  the  Cervidae. 

Even  though  animals  with  antlers  are  met  with 
as  early  as  the  Miocene,  still  the  more  complete 
development  of  true  Deer  belongs  to  very  recent 
periods,  and  this  explains  their  geographical  dis- 
tribution in  the  main.  In  addition  to  the  circum- 
polar  reindeer  and  elk,  Eiitimeyer,  agreeing  with 
Brooke,  reckons  twenty  species  to  America  and 
thirty-nine  to  the  Old  World,  many  of  which  are 
certainly  doubtful.  An  exchange  between  East 
and  West  seems  evident,  and  yet,  as  we  have  seen, 
it  was  extremely  limited.  The  remarkable  want  of 
deer  in  Africa  beyond  the  desert,  would  have  to  be 
explained,  with  Wallace,  by  the  fact  that  there  must 
have  existed  obstacles  almost  insurmountable  to 
the  animals  when  they  first  began  to  distribute ; 
on  the  other  hand,  antelopes  and  even  giraffes 
•had  either  already  passed  the  open  road  south- 
wards, or,  owing  to  their  organisation,  had  gra- 

1  Brooke,  '  On  the  Classification  of  the  Cervidae,'  Proc.  Zool. 
Soc.  1878. 


THE  CERVID.E,  OR  DEER.  167 

dually  overcome  the  difficulties  presented  by  the 
desert. 

Zoologists  have  always  classed  the  Musk  Deer 
and  the  Dwarf  Musk  Deer  (Tragulidce)  with  the  true 
stags,  although  they  are  hornless  animals.  In 
doing  this  they  have  allowed  themselves  to  be  led 
by  the  general  impression  that  the  possession  of 
antlers  is  not  determinative  of  the  relationship  ; 
this  had  already  been  affirmed  by  Alphonse  Milne- 
Edwards  in  1864,  and  has  been  proved  by  their 
connection  to  the  fossil  forms  that  have  now  been 
brought  to  light.  From  these  annexed  groups  the 
Hycemoschus  aquaticus,  which  lives  on  the  west 
coast  of  Africa,  is  of  great  importance  as  the  con- 
necting link  between  the  present  and  the  remote 
past.  Our  Figure  25,  A,  gives  the  left  fore-foot  of 
this  animal.  Hycemoschus  is  also  a  decided  two- 
hoofed  animal,  although  the  two  middle  metacarpals 
(in,  iv)  are  entirely  separate,  and  although  the 
two  outer  metacarpals  (n,  v)  are  perfectly  com- 
plete and  the  two  lateral  toes  are  developed  and 
connected.  Hycemoschus  thus  proves  itself  an 
adaptive  form,  inasmuch  as  the  two  toes  that  are 
no  longer  of  use  have  ceded  their  right  to  the 
tarsals,  to  the  principal  toes,  and  thus  increased  the 
strength  of  the  latter.  The  skeleton  of  the  fore- 


168 


THE  MAMMALIA. 


foot  of  the  Hyamosclms   appears  a  slight  modifi- 
cation of  that  of   the  Miocene  Hyopotamus  (Fig. 


FIG.  25 

A.  Left  fore-foot  of  Hya&moschus  aquations. 

J5.  Same  foot  of  Hyopotamus.    After  Kowalewsky. 


THE  CERVID^E,  OR  DEER.  169 

25,  B).  There  both  outer  toes  are  still  somewhat 
longer  and  stronger.  Trapezoid  and  os  magnum 
have  not  yet  coalesced ;  the  metacarpals  n  and  v 
are  still  connected  with  the  carpals.  Upon  the  whole, 
however,  the  differences  between  the  living  and  the 
Miocene  representatives  of  the  pair-hoofed  group 
are  so  slight  that  Hycemoschus  may  be  called  a 
surviving  form  of  primary  ruminant. 

The  hind  limbs  of  the  Hycemoschus  are  more 
changed  than  the  front  limbs,  owing  to  the  two 
principal  metatarsals  having  almost  completely 
coalesced.  A  greater  reduction  of  the  hind  limbs 
is  often  met  with :  for  instance,  the  peccary  has 
only  one  rudimentary  toe  on  its  back  foot,  whereas 
there  are  two  on  the  fore-foot.  This  difference  in 
the  construction  of  the  front  and  back  limbs  is,  we 
think,  to  be  explained  by  the  greater  amount  of 
work  which  the  hind  legs  have  to  accomplish ;  for, 
as  was  said  above,  we  look  upon  a  reduction  of  this 
kind  as  an  advance  in  the  power  of  the  adaptation. 
But,  while  we  are  naturally  led  back  from  our 
present  Deer  and  Tragulidse  to  those  early  four- 
toed  Hyopotamidae,  we  do  not  in  any  way  mean  to 
affirm  that  up  to  the  Middle  Tertiary  all  animals  of 
the  Ruminant  group  without  horns  or  antlers 
possessed  the  full  number  of  four  toes.  On  the 


170  THE  MAMMALIA. 

contrary,  it  is  found  that  the  Anoplotherium  from 
the  Eocene  of  the  Paris  limestone,  which  has  left 
no  descendants,  shows  scarcely  any  traces  of  the 
second  and  fifth  toes ;  and  by  the  side  of  the 
Hyopotamus,  with  four-toed  feet,  there  existed  the 
distinctly  two-toed  Gelocus,1  whose  extremities  are 
almost  as  much  reduced  as  the  Deer ;  and  the  same 
is  the  case  with  Diplopus.  It  would  be  rash  to 
attempt  to  determine,  among  all  these  varied  forms, 
which  was  the  actual  and  definite  primary  form  for 
the  Deer  or  any  other  living  group  of  the  Eumi- 
nants ;  still,  any  attempt  to  explain  the  striking 
relation  between  the  past  and  present  forms,  other- 
wise than  by  means  of  the  theory  of  descent  and 
in  accordance  with  Darwin's  principle,  cannot  be 
expected  from  us.  The  share  which  homceogenetic 
approximation  may  have  taken  in  this  connection 
has  already  been  discussed. 

The  same  result  is  obtained  by  the  condition  of 
the  teeth;  and,  as  in  the  case  of  the  limbs,  the 
teeth  must  not  be  examined  in  the  Deer  by  them- 
selves, the  whole  group  of  Kuminants  must,  first 
of  all,  be  compared  with  the  fossil  forms. 

Among  our  living  Hoofed  animals  the  Giraffe 

1  Filhol,  '  Mammif^res  fossiles   de  Eonzon,  1882,'   Gelociis, 
Ancodus,  and  others ;  their  Relation  to  Hyopotamus. 


THE  CERVID^E,  OR  DEER.  171 

occupies  a  perfectly  isolated  position.  Apart  from 
its  strange  shape — the  result  of  a  lengthening  of  the 
vertebrae  of  the  neck — and  of  the  different  lengths 
of  its  fore  and  hind  limbs,  descriptive  zoology 
has  very  rightly  laid  stress  upon  the  frontal  deco- 
rations which  adorn  both  sexes,  and  which  have 
been  said  to  be  neither  horns  nor  antlers.  The 
two  horn-like  unbranched  protuberances  are 
covered  with  a  hairy  skin  which  never  dries  up  as 
in  the  case  of  the  deer,  and  hence  they  do  not -fall 
off  periodically.  These  skin-covered  bony  protuber- 
ances cannot,  however,  be  compared  to  the  bony 
protuberances  of  the  Oxen,  as  might  be  supposed, 
that  is,  to  the  processes  of  the  frontal  bone  covered 
by  the  horn  sheath.  On  the  contrary,  like  the 
antlers  proper,  they  begin  as  ossifications  of  the 
skin,  and  grow  precisely  in  the  same  manner  as 
antlers,  but  never  become  perfectly  attached  to  the 
frontal  bone.  In  order  briefly  to  distinguish  the 
character  of  the  formations  it  may  be  said  that — 

Hollow-horned  animals  have  frontal  processes 
without  antlers, 

The  Deer  processes  with  antlers, 
The  Giraffes  antlers  without  processes. 
Hence  Eiitimeyer  calls  the  giraffes  '  a  most  fantastic 
form  of  deer.' 


172  THE  MAMMALIA. 

Like  the  lions  and  gazelles,  the  giraffes  of 
Africa  are  probably  immigrants  from  the  South  of 
Europe.  Among  the  Mammalia  buried  at  Pikermi 
is  a  species,  Camelopardalis  attica,  almost  the  same 
size  as  the  African  variety.  Unfortunately  its  skull 
is  not  known.  The  disproportion  between  the 
hind  and  fore  limbs  seems  to  have  been  even 
greater  in  the  fossil  species.  Further  traces  lead 
us  to  the  Siwalik  hills  in  India.  Numerous  re- 
mains have  enabled  Gaudry  to  restore  the  com- 
plete skeleton  of  a  genus  closely  allied  to  the 
giraffe — the  Helladoiherium — which  lived  in  herds 
in  Miocene  Attica,  and  owing  to  their  great  size 
must  have  been  characteristic  figures  in  the  land- 
scape of  the  primeval  world. 

It  was  customary  to  class  with  the  above  the 
colossal  Indian  Sivatherium,  which  possessed  a  pair 
of  simple  horns  in  front,  and  a  second  branched 
pair.  And  yet  our  conjectures  with  regard  to  its 
affinity  with  the  Giraffe  are  uncertain,  and  Ptiiti- 
meyer  thinks  that  the  Sivatherium  points  as  much 
to  the  Antelopes,  as  the  Giraffes  to  the  Deer.  Our 
knowledge  of  two  other  Indian  species,  the  Brama- 
therium  and  Hydaspitherium,  is  as  yet  so  fragmen- 
tary that  it  is  wiser  not  to  make  any  conjecture 
as  to  their  relationship. 


THE  ANTELOPES  AND  OXEN.        173 

The  Giraffes  stand  close  to  the  Deer,  not  because 
they  have  branched  off  from  the  deer,  but  because 
the  unknown  ancestors  on  both  sides  showed  a 
disposition  to  certain  reductions  and  convergences 
of  a  similar  kind. 

6.   CAVICORNIA,   HOLLOW   HORNED   ANIMALS. — ANTELOPES 
AND   OXEN. 

The  horned  Ruminants,  which  are  grouped 
round  the  Chamois,  Sheep,  and  Oxen — and  hence 
furnished  with  horn-cores  rising  from  the  frontal 
bones,  and  a  horn  sheath — would  appear  to  any- 
one to  form  a  natural  group.  And  even  those  who 
have  not  studied  the  subject  would  undertake  to 
distinguish  a  Gazelle,  as  the  representative  of  the 
Antelopes,  from  an  Ox.  The  gracefulness  of  its  whole 
appearance,  more  particularly  of  the  horns,  the 
smallness  of  the  head,  the  slender  shape  of  the  legs, 
sharply  distinguish  the  Antelopes  from  the  Oxen, 
whose  horns  stand  at  the  outermost  point  of  the 
brow,  whose  skull  is  unwieldy  in  form,  and  whose 
legs  (in  keeping  with  the  rest  of  the  skeleton)  are 
anything  but  graceful.  However,  when  we  examine 
the  different  families  in  any  good  collection,  we 
shall  find  that  by  the  side  of  the  prevailing  type 
of  the  slim  antelope,  there  are  various  kinds  of 
cow-shaped  forms,  with  head  and  limbs  in  no  way 


174  THE  MAMMALIA. 

resembling  the  Gazelles,  yet  almost  all  with  horns 
strikingly  different  from  those  of  Oxen.  Finally, 
the  gnu  completely  breaks  down  any  systematic 
boundary,  for  by  the  form  of  its  hindquarters  and 
tail  it  resembles  the  horse.  And  into  this  group 
sheep  and  goat  have  to  be  brought.  We  can,  it 
is  true,  distinguish  them  among  one  another  by 
the  characteristic  traits  of  the  family ;  for  instance, 
by  the  peculiar  form  of  the  skull.  The  ram,  owing 
to  the  form  and  solidity  of  the  nasal,  lachrymal, 
and  frontal  bones,  is  able  to  give  and  to  receive 
those  tremendous  blows  of  forehead  against  fore- 
head which  would  break  the  skull  of  the  male 
goat.  But  there  are  sheep  with  goat-like  horns; 
and  an  animal  that  is  clearly  a  sheep  from  the 
form  of  its  skull  has  up  to  within  recent  times 
been  called  the  musk  ox. 

These  resemblances — it  may  positively  be  as- 
serted— do  not  proceed  from  recent  derivation  or 
crossings,  but  must  be  traced  back — except  in  the 
case  of  the  closely  allied  Sheep  and  Goats — to  con- 
vergences. Moreover,  the  Antelopes — the  most 
varied  group  of  the  living  Euminants — have  not 
been  so  carefully  studied  in  connection  with  their 
nearest  fossil  relatives  as  the  Oxen.1 

1  Biitimeyer's  valuable  investigations  of  this  group  may  hore 
be  mentioned. 


THE  ANTELOPES  AND  OXEN. 


175 


The  distinguishing  feature  in  the  skull  of  the 
ox  is  most  strongly    developed  in   our    domestic 


FIG.  26.— Skull  of  a  Short-horned  Bull. 
/.Frontal  bone ;  n,  nasal  bone ;  o,  upper  jawbone  ;  z,  mid  jawbone. 


176  THE  MAMMALIA. 

animal  belonging  to  the  genus  Bos  (Fig.  26).  Here 
the  parietals  are  pushed  completely  back  from  the 
top,  or  all  but  a  small  portion,  to  the  abrupt 
incline  at  the  back  of  the  head.  From  a  front 
view,  or  looked  at  from  above,  they  cannot  be 
seen  at  all.  On  the  other  hand,  the  frontal 
bones  (Fig.  26)  form  great  plate- shaped  cover- 


Fio.  27.— Skull  of  the  Gazelle  (Antelope  arabica). 
*,  Parietal ;  /,  frontal  bone  ;  z,  mid  jawbone. 

ings  to  the  forehead,  and  the  bony  processes  rise 
upon  their  outer  edge.  As  compared  with  the 
skull  of  an  antelope  (Fig.  27),  the  skull  of  our 
domestic  ox  has  reached  the  extreme  of  a  formation 
which  is  still  repeated  pretty  perfectly  in  the 
individual  development  of  the  calf  to  the  cow.  It 
consists  in  this  :  that  in  the  calf  the  skull  is  still 


THE  ANTELOPES  AND  OXEN.       177 

rounded,  the  frontal  part  is  not,  as  yet,  elongated, 
and  the  crown  portion  still  forms  actually  a  part  of 
the  upper  covering  of  the  skull.  Only  upon  the 
appearances  of  the  horn-cores  and  the  lengthening 
of  the  frontal  bones  do  we  find  the  first  indication 
of  the  abrupt  rising  up  of  the  main  back  wall. 
The  calf  is  therefore  still  ant  elope- shaped  as 
regards  the  formation  of  its  skull,  as  is  shown  in 
Fig.  27,  where  the  whole  length  of  the  parietal 
bones  are  still  to  be  seen  from  above,  and  the  horn- 
cores  do  not  occupy  the  backmost  or  outermost 
corner  of  the  frontal  bones.  Sheep  and  goats  also 
keep  within  the  boundary  of  this  type  of  the  Ante- 
lope family.  Calf  and  cow,  therefore,  again  corro- 
borate the  most  important  proposition  of  our  doc- 
trine of  descent :  that  the  individual  development 
is  an  abridged  repetition  of  the  historical  develop- 
ment of  the  species. 

On  the  accompanying  table  of  Kiitimeyer's  we 
have  the  sub-families  of  the  Oxen  classed  according 
to  the  form  of  their  skulls.  It  begins  with  the 
buffaloes,  which,  as  regards  skull  and  the  position 
of  their  horns,  have  deviated  least  from  the  Ante- 
lopes, and  closes  with  the  domestic  ox,  which  has 
differentiated  the  most.  We  gather  from  this 

table— which  contains  the  quintessence  of  all  the 
17 


178 


THE  MAMMALIA. 


TABULAR  VIEW  OF  THE  FOSSIL  AND  LIVING  OXEN 
(AFTER  EUTIMEYER). 


Miocene  ? 
Pliocene 

Pleistocene 

Living 

I.  Bubalina 

Bubalus 

caffer 

Buffelus 

antiquus 
sivalensis 

brachyceros 
indicus  (domestic 

ox) 

sondaicus 

Pallasii 

Probubalm 

triquetri- 

rostris 

Amphibos 

acutiformis 

antelopinus 

(Anoa)  celebensis 

II.  Portacina 

Leptobos 

Falconer! 

Strozzi 

Frazeri 

[II   Bibovina 

Bibos 

etruscus 

Palaeo- 

Gaurus 

Gaurus 

?  Gavaeus 

sondaicus 

indicus 

grunniens  (Yak) 

[V.  Bisontia 

Bison 

sivalensis 

prisons 

europfBus 

latifrons 

americanus 

V.  Taurina 

Bos 

planifrons 

namadicus 

primigenius 

taiirus    f.  primi- 

genius 

f.  trochocerus 

investigations  made  on  the  subject — that  our  know- 
ledge is  still  meagre  enough,  inasmuch  as  at  the 
Pliocene  stage — where  true  oxen  are  first  met  with 
— we  already  find  the  transition  from  the  buffalo 
to  the  ox  in  its  narrower  sense.  The  different 


THE  ANTELOPES  AND  OXES.  179 

European  oxen l  have  all,  perhaps,  to  be  traced  back 
to  the  Diluvial  Urus,  or  wild  bull  (Bos  primigenius), 
and  the  races  which  branched  off  as  early  as  the 
Diluvial  period.2  If,  in  accordance  with  the  above 
standpoints,  the  skull  of  the  domestic  ox,  of  the  bison, 
the  yak,  and  the  Indo-European  buffalo,  be  com- 
pared with  that  of  the  antelope,  it  will  be  found  that 
the  resemblance  to  the  antelope  will  become  more 
and  more  apparent.  Thus  the  bison  (Fig.  28)  is 
still  so  like  the  ox  that,  as  we  shall  see,  it  might 
be  doubted  whether  one  of  our  races,  the  Dux 
cattle  of  Eastern  Tyrol,  is  to  be  traced  back  to  the 
wild  bull  or  to  the  bison.  On  the  other  hand,  the 
Anoa  of  Celebes,  which  Biitimeyer  calls  the  Probu- 
balus  celebensis,  is  indeed  still  an  ox  in  all  its  out- 
ward characteristics  ('  the  dwarf  of  the  ox  family '), 
but  is  a  complete  antelope,  as  regards  the  position 
of  its  frontal  and  parietal  bones  (Fig.  29).  This 
agreement  in  the  outward  parts  must  scientifically 

1  The  three  most  important  races  of  oxen  which  have  to  be 
traced  back  to  Bos  primigenius  are  :       , 

Brachyceros  race          .        .         .    Appenzell  cattle 
Primigenius  race          .        .        .    Holland  cattle 
Frontosus  race     ....    Bern  cattle 

2  A  good  survey  of  the  investigations  and   opinions  as  to  the 
origin  of  the   domestic   ox  is  given  in  Friihling's  Landwirth- 
schafllicher  Zeitung,   Feb.    1878;    Pagenstecher,  Studien  zum 
Ursprung  des  Rindes. 


180 


THE  MAMMALIA. 


be  regarded  as  a  convergence,  in  the  skull  as  an 
homology. 


Fio.  28.  —Skull  of  the  Bison  americanus.    After  Wilckens. 

It  has  been  stated  that  the  separation  of  the 


THE  ANTELOPES  AND  OXEN. 


181 


antlered  from  the  horned  animals  is  met  with  first 
in  the  Miocene,  or,  in  other  words,  that  deer  and 
antelopes  are  difficult  to  distinguish  before  that 
period.  Later  we  have  the  branching  off  of  the 
oxen,  but  we  cannot  closely  define  the  point  of 


FIG.  29.-  Skull  of  the  Anoa.    After  Kiitimeyer. 
*,  Parietals ;  /,  frontal  bone. 

attachment.  In  the  Lower  Miocene  and  Eocene, 
the  Ruminants  are  represented  by  distinctly  pair- 
hoofed  and  crescentic-toothed  animals,  which, 
although  absolutely  without  horn- cores  on  the 
frontal  bones,  are  distinguished  by  a  very  full 
dentition  without  gaps,  some  being  without  the 


182  THE  MAMMALIA. 

prominent  canine  teeth  which  serve  the  others  as 
weapons.  An  early  Selenodont  (crescentic-toothed) 
animal  of  this  kind  for  the  primeval  pair -hoofed 
group — one  which,  like  the  Hyopotamus,  does  not 
belong  distinctly  to  any  special  type — is  the  genus 
Cainotherium,  an  animal  of  the  most  graceful  shape ; 
we  have  probably  a  correct  picture  of  its  appear- 
ance in  the  living  dwarf  musk-animals  (Fig.  30). 
That  Cainotherium  and  its  relatives,  e.g.  Xipho- 
don,  Xiphodontherium,  were  Kuminants,  cannot  be 
doubted  from  the  position  and  nature  of  the 
tranverse  ridges  of  their  molars,  also  from  the 
character  of  the  joints  of  the  jaw  upon  which 
depends  the  peculiar  action  of  the  grinders.  The 

dental  formulae  is  i  -,   c  -,    p  -,  m  -,  and  in  most 
o        1          4        o 

specimens  they  stand  in  closed  rows  in  both  jaws. 
Now  our  present  hollow-horned  animals  have  no 
incisors  in  the  upper  jaw,  and  no  canines  either  in 
the  upper  or  lower  jaw,  and,  moreover,  they  occur 
in  the  upper  jaw  only  in  some  species  of  deer.  The 
diminution  of  the  teeth — a  very  general  pheno- 
menon— must,  therefore,  have  taken  place  gradu- 
ally in  the  course  of  ages.  How  and  when  this 
occurred,  Filhol !  has  very  clearly  pointed  out  with 

1  Compare  p.  64,  note  2. 


THE  ANTELOPES  AND   OXEN. 


183 


respect  to  the  above-mentioned  animals.  The 
Cainotheria,  to  judge  from  the  quantities  of  their 
remains,  must  have  lived  in  herds  after  the 
manner  of  the  Antelopes ;  hence  hundreds  of  skulls 
and  thousands  of  lower  jaws  could  be  compared. 
Further,  an  extraordinary  variability  was  found 


FIG.  30. — Skull  of  Cainotherium  metopias.    Nat.  size  (after 
Fiihol). 

in  the  canine  tooth  (Fig.  30,  c),  and  in  the  front 
premolars.  The  normal  row  of  teeth,  i.e.  the  teeth 
inherited  from  early  times,  begins  to  show  gaps; 
a  small  gap  occurs  between  the  canine  and  the 
first  premolar ;  the  latter  then  moves  towards  the 
canine ;  frequently  the  second  premolar  follows ; 
both  thus  obviously  become  useless,  and  the  next 


184  THE  MAMMALIA. 

stage  is  their  total  disappearance.  Further,  we 
then  see  indications  of  the  brow  weapons,  in 
correlation  with  the  loss  of  the  canines.  Filhol 
here  reminds  us  of  the  proposition  expressed 
even  by  Aristotle,  and  formulated  again  at  the 
beginning  of  this  century  by  Etienne  Geoffrey  St. 
Hilaire  with  regard  to  the  balancing  of  the  organs 
(balancement  des  organes).  With  the  loss  of  the 
front  premolars,  the  permanent  molars  become 
more  regularly  developed,  and  it  is  thus  that  the 
now  typical  ruminant  jaw  has  been  farther  and 
farther  developed ;  the  ancient  form — owing  to 
complete  rows  of  teeth  and  the  more  marked 
canines— still,  in  some  measure,  resembled  the 
jaw  of  the  Omnivora  and  the  Bunodonts  (animal 
with  tuberculate  teeth). 

From  Filhol' s  observations  we  find  that  this 
process  of  the  gradual  formation  and  the  fixing  of 
the  gap  in  the  dentition  of  the  Euminants  has 
repeated  itself — that,  at  first,  individual  modifica- 
tions became  established  by  inheritance,  and  led 
to  the  formation  of  races.  And  although  we 
cannot,  in  every  instance,  trace  the  given  advan- 
tages connected  with  the  modifications,  and  that 
led  to  the  selection,  still,  as  was  shown  above,  we 
have  some  idea,  as  well  as  some  explanation,  of 


THE  ANTELOPES  AND  OXEN.  185 

the  advantages,  and  they  account  for  the  gradual 
disappearance  of  the  primary  groups  and  for  the 
origin  of  new  species. 

In  America  we  find  the  same  circumstances. 
Antelopes  and  oxen  have,  it  is  true,  decreased  in 
a  remarkable  manner  among  the  present  American 
fauna,  but  the  abundance  of  the  fossil  forms  is  so 
great  that  we  can  scarcely  find  fault  with  the 
patriotism  of  the  American  naturalists,  when  we 
find  thenij  in  this  case  also,  claiming  their  country 
to  have  been  the  cradle  of  this  group  of  Hoofed 
animals.  Of  purely  American  types  we  will  name 
only  the  very  numerous  family  of  the  Oreodonta, 
which  combines  traits  of  the  pig-shaped  pair- 
hoofed,  or  thick-skinned  animals,  i.e.  the  large 
canines  as  weapons,  and  molars  of  the  ruminant 
type.  They  were  so  numerous  in  the  Middle  Eocene 
that  one  stratum  has  been  called  after  them,  and, 
together  with  this  force  of  numbers,  they  show 
that  tendency  to  differentiate  into  races  and 
species  which  seems  to  be  characteristic  of  pri- 
mary forms. 

Although  America  was  rich  in  the  still  indefinite 
precursors  of  our  present  Euminants,  it  has  re- 
mained absolutely  unproductive  as  regards  Oxen. 
For  even  the  Diluvial  ancestor  of  the  North  Ameri- 


186  THE  MAMMALIA. 

can  bison  might  be  disputed  as  belonging  to  America. 
This  naturally  touches  upon  extremely  important 
points  in  anthropology  and  the  history  of  civilisa- 
tion, particularly  in  connection  with  the  other  cir- 
cumstance that  the  line  of  horses  was  broken  off 
precisely  at  the  point  where  the  American  Man  first 
appeared  on  the  scene ;  and  moreover  when  he  was 
still  in  so  rude  and  helpless  a  state  that  he  could 
not  have  brought  either  one  or  the  other  of  his 
fellow- workers  with  him  from  his  Asiatic  home,  to 
aid  him  in  his  further  advance  in  civilisation. 
Hence  the  same  phenomenon,  as  was  shown  above 
to  have  occurred  in  Australia,  has  been  repeated 
here,  even  though  in  a  less  striking  manner.  Even 
at  the  beginning  of  our  century,  buffaloes  (Bison 
americanus)  crossing  the  prairies  were  to  be  counted 
by  hundreds  of  thousands.  Nothing  points  to  the 
fact  that  the  American  aborigines  ever  made  any 
attempt  to  tame  these  wild  creatures.  It  would 
seem  rather  that  throughout  the  whole  of  North 
America  the  Indian  was,  in  a  manner,  chained  to 
the  buffalo,  and  that  from  year  to  year  he  had  to 
pass  from  one  pasture  to  another  with  the  animal. 
Hence  it  was  impossible  that  the  higher  civilisation 
of  a  settled  life  could  take  the  place  of  a  huntsman's 
career.  Only  those  tribes  which  wandered  from 


THE  ANTELOPES  AND  OXEN.       187 

the  north  southwards,  to  central  and  to  one  part  of 
South  America,  could  attain  any  comparatively  high 
development  of  civil  life ;  and  this  was  owing  to  the 
more  favourable  climatic  circumstances,  and  to 
various  species  of  llamas  having  been  made  use  of 
as  domestic  animals. 

The  introduction  of  oxen  and  of  horses  from 
Europe  was  the  beginning  of  the  end  of  the  Ameri- 
can bison.  The  bison  has  found  its  biographer  in 
Professor  Allen,1  who  has  clearly  pointed  out  its 
relation  to  the  Diluvial  races ;  and  as  regards  this 
relation  Allen  arrives  at  a  somewhat  different  con- 
clusion to  what  Eiitimeyer2  does.  The  earliest  form 
is  the  gigantic  Bison  latifrons  from  the  Diluvial  strata 
of  North  America,  where  also  are  found  the  remains 
of  mastodon,  megalonyx,  mylodon,  and  others.  It 
produced  species  (races?)  not  very  different  from 
one  another,  the  Bison  antiquus  of  the  New  World, 
and  the  B.  pnscus  of  the  Old  World.  The  latter 
is  the  progenitor  of  the  Europe- Asiatic  urus  or 
wild  bull ;  the  Bison  antiquus,  which  lived  contem- 
poraneously with  the  Elephas  primigenius,  is  the 
progenitor  of  the  Bison  americanus. 

It  is  very  probable,  as  already  remarked,  that 

1  Allen,  The  American  Bison.     Cambridge,  Mass.,  1876, 

2  See  above,  p.  178. 


188  THE  MAMMALIA. 

the  original  inhabitants  of  America  did  not  make 
any  attempts  to  tame  the  buffalo.  At  all  events, 
they  did  not  succeed  in  doing  so.  Very  different 
have  been  the  results  of  the  attempts  of  the  Euro- 
pean immigrants,  who  have  repeatedly  been  engaged 
in  this  task  since  the  middle  of  last  century.  They 
have  succeeded  pretty  easily  in  obtaining  a  cross 
between  the  wild  and  the  domestic  animal,  by 
allowing  the  captured  young  ones  to  grow  up  in  the 
herd ;  and  it  seems  certain  that  this  will  produce 
a  strong  cross-breed.  A  Mr.  Thompson,  who,  ac- 
cording to  Allen,  had  watched  the  attempts  at 
domestication  of  the  unmixed  species  during  fifty 
years,  has  expressed  his  conviction  that  the  animal 
is  capable  of  being  employed  for  work  as  well  as 
for  yielding  milk,  while  the  earlier  attempts  at  cross- 
breeding were  made  principally  with  a  view  to  the 
horns  and  skins  of  the  animals. 

Under  these  circumstances,  it  seems  natural  that 
the  question  should  arise  as  to  whether  one  or  the 
other  race  of  the  European  ox  must  not  be  traced 
back  to  the  bison.  All  those  who  have  carefully 
studied  the  question  declare  the  bison  to  be  unfit 
for  domestication,  and  have  referred  all  the  different 
races  of  the  domestic  ox — with  the  exception  of 
the  yak — to  the  genus  Bos  distinguished  by  the 


THE  ODD-HOOFED  ANIMALS.  189 

characteristic  formation  of  the  forehead.  Wilckens 
alone1  has  drawn  attention  to  the  resemblance 
between  the  skull  of  the  short-headed  cattle  of 
Eastern  Tyrol  (Dux)  and  that  of  the  bison,  and 
thinks  that  further  investigations  would  furnish  a 
complete  proof  for  this  derivation. 

Perissodactyla,  or  Odd-hoofed  Animals. 

The  Odd-hoofed  animals  are  at  present  repre- 
sented by  three  groups :  Tapir,  Khinoceros,  and 
Horse,  all  of  which  are  poor  in  species.  The  re- 
duction in  the  fore  and  hind- foot  has  advanced 
farthest  in  the  horse ;  the  middle  toe,  owing  to  the 
complete  disappearance  of  the  others,  has  become 
the  sole  support  for  the  weight  of  the  body.  There 
exist  only  the  mere  rudiments  of  the  metatarsals 
of  the  second  and  fourth  toe.  The  tapir  comes 
first  with  four  toes  on  the  fore-foot,  and  three  on 
the  hind-foot;  the  rhinoceros  has  three  toes  on 
both  the  fore  and  the  hind  limbs,  and  both  these 
groups  have  preserved  very  ancient  characteristic 
features.  But  in  spite  of  its  transformation  having 
advanced  so  far,  no  other  mammal  of  the  present 

1  Wilckens,  '  Ueber  die  Schadelknochen  des  Eindes  aus   den 
Pfahlbauten  des  Laibacher  Moqres,  1877  '  (Communications  to 
the  Anthropological  Society  of  Vienna). 
18 


190  THE  MAMMALIA. 

day  can  show  as  distinct  or  regular  a  pedigree  as 
the  horse.  By  means  of  the  accompanying  table 
we  will  endeavour  to  solve  our  problem.-  The  con- 
nections are,  upon  the  whole,  so  simple  and  clear 
that,  although  palaeontologists  may  differ  in  the 
explanation  of  the  relationships,  these  differences 
refer  merely  to  subordinate  points. 

TABLE  SHOWING  THE  CONNECTION  BETWEEN  THE  ODD -HOOFED  ANIMALS. 

Present  Time 
Diluvium 

Tapir 
Miocene 


Eocene  Paleeotherida?  (four  and  three  toed) 

Anti-Eocene  odd-hoofed  animals 
1  American  line  of  horses. 


1.   TAPIE  AND  RHINOCEROS. 

Of  Tapirs  we  have  two  or  perhaps  three  species 
in  South  America,  and  one  in  India.  Their 
favourite  haunts  are  moist  forests.  Their  dentition 
is  very  complete  in  spite  of  a  considerable  gap 
between  the  canines  and  molars.  The  dental  for- 

mulais:  i    ,  '    ,  ™  ~ 


>vr         Rhinoceros 

Horse 

Elasmotherium 
IHipparion 

Pliohippus  ' 
Protohippus 

Aceratherium 
iodon                     f 

Anchitherium 

Palffiotherium  med. 
Palaeotherium 

Miohippus 
Mesohippua 
Orohippus 
Eohippus 

THE  TAPIR  AND  RHINOCEROS.  191 

The  incisors  and  canine  teeth  are,  as  usual,  not 
of  any  special  form  or  construction,  whereas  the 
cheek-teeth  show  a  very  peculiar  type  by  the 
marked  character  of  two  transverse  ridges,  the  tops 
of  which,  hoth  inside  and  outside,  hecome  tolerably 
sharp  tubercles  (Fig.  32).  The  ridges  of  the  upper 
teeth  are  situated  on  the  front  and  in  the  middle 


FIG.  31.— Skull  of  the  Tapir  (Tapirus  americanus). 
n,  Nasal  bone  ;  t,  bony  wall  separating  the  nasal  cavities. 

of  the  crown ;  they  fit  into  the  grooves  of  the  lower 
molars,  where  the  back  ridge  rises  from  the  back 
wall  of  the  tooth.  The  grinding  movement  peculiar 
to  the  Kuminants  can  be  accomplished  by  the  tapirs 
only  in  a  very  slight  measure ;  on  the  other  hand, 
their  teeth  are  specially  adapted  for  crushing  vege- 
table substances,  which  can  also  be  roughly  cut  by 


192  THE  MAMMALIA. 

the  sharp  ridges  of  the  crowns  of  their  teeth. 
Although  the  fore-foot  of  the  tapir  possesses  four 
perfect  toes,  still,  from  an  examination  of  the 
skeleton  of  the  foot,  it  becomes  evident  at  once  that 
the  second  toe  from  the  inner  side,  corresponding 
with  the  middle  toe  of  the  five-toed  limb,  is  more 
strongly  developed  than  the  rest,  and  that  it  stands 
in  that  peculiar  position  which  we  have  shown  to 


1     i 

FIG.  32. — Back  Molar  of  the  Lophiodon  parisiensis,  on  the  left 

from  below. 
A,  a,  Front  and  back  outer  tubercle ;  /,  i,  front  and  back  inner  tubercle. 

be  the  distinguishing  feature  in  the  Odd-hoofed 
animals.  A  five-toed  genus  with  the  middle  toe  in 
this  position  has,  as  we  have  seen,  been  preserved 
in  the  Coryphodon  from  the  Eocene  formation. 
Now,  as  the  lowest  known  tapir-shaped  animals 
possess  at  most  four  toes,  the  unknown  primary 
forms  must,  of  course,  be  looked  for  in  the  secon- 
dary divisions.  The  tapir,  in  addition  to  having 
lost  the  inner  toe,  has  also  lost  the  fifth  toe ;  this 


THE  TAPIR  AND  RHINOCEEOS.  193 

is  another  instance  of  the  law  laid  down  on  p.  169, 
that  the  hind  extremities  are  more  readily  and 
more  frequently  reduced  than  the  fore  limbs. 

In  the  tapir  we  have  an  animal  from  the  Early 
Tertiary  period  that  has  remained  almost  wholly 
unchanged,  one  of  those  species  which  have  been 
called  permanent,  and  which  are  more  frequently 
met  with  in  the  lower  animal  world.  They  do  not 
prove  the  invariability  of  the  species,  but  prove 
only  that  under  certain  circumstances  the  stability 
of  the  species  can  be  of  an  extremely  long  duration. 
In  the  Miocene  the  genus  is  represented  by  several 
good  species.  In  the  Middle  Eocene,  we  have  in  its 
place  the  Lophiodon,  which  is  characterised  by  a 
still  greater  simplicity  of  the  ridges  of  the  teeth, 
and,  as  regards  appearance  generally,  may  have 
been  scarcely  distinguishable  from  the  tapir.  The 
European  Lophiodonts  naturally,  in  the  first  place, 
lead  over  to  the  Indian  caparisoned  tapir.  The 
American  ancestral  line  of  the  tapirs  is  more  com- 
plete. Two  genera,  Helaletes  and  Hyrachyus, 
closely  related  to  Lophiodon,  belong  to  the  Eocene. 
They  may  be  called  tapir oid  forms.  At  a  somewhat 
later  period  appears  Lophiodon,  one  of  the  few 
genera  we  have  in  common.  Still  more  tapiroid 
in  form  is  the  Miocene  Tapiravus,  which  in  the 


194  THE  MAMMALIA. 

Post  Tertiary  is  followed  by  the  tapir  itself.  That 
the  animal  migrated  to  its  present  home  in  South 
America  is  probably  certain.  Now  Eocene  races 
existed  in  the  Eastern  as  well  as  in  the  Western 
Hemisphere,  whose  origin  and  separation  is  in- 
deed unknown,  but  the  form  and  character  of 
the  feet  and  teeth  would  require  but  small 
changes  to  produce  the  genus  Tapir.  Hence  it  is 
here  again  merely  a  matter  of  opinion  (owing  to 
the  present  state  of  our  knowledge)  whether,  with 
Marsh,  we  consider  it  more  likely  that  the  original 
home  of  the  tapirs  is  assigned  to  the  New  World, 
and  that  they  are  supposed  to  have  migrated  to 
Asia,  or  vice  versa ;  or  again,  if,  with  Carl  Vogt,  a 
parallel  development  is  considered  the  more  prob- 
able hypothesis. 

By  the  side  of  our  present  tapirs,  and  unmistak- 
ably allied  to  them  in  the  formation  of  foot  and 
dentition,  stand  the  Rhinoceroses,  which  are  dis- 
tributed over  Southern  Asia,  with  its  large  islands, 
and  Africa.  The  head  weapons  are  solid  horny 
projections  of  the  nasal  bone,  which  rise  into  a 
flat  hump  within  equalities  of  the  bone  substance. 
From  this  characteristic  feature  it  can  in  most 
cases  be  determined  whether  the  fossil  animals  of 
the  Ehinoceros  species  possessed  horns. 


THE  TAPIE  AND  KHINOCEROS.  195 

Throughout  the  whole  of  the  Diluvium  and  the 
Tertiary  period  up  to  the  Palaeotheriae  and  Lio- 
phodons,  there  existed  rhinoceroses,  or  hornless 
animals  closely  related  to  them.  Midway  in  the  line 
stands  the  hornless  Aceratherium.  Its  connection 
with  the  Palseotheridse  and  the  Tapiridae  becomes 
at  once  apparent  from  an  examination  of  the  skull  ; 
still,  a  diminution  of  the  front  and  canine  teeth 
has  taken  place.  In  fact,  the  whole  family  of  the 
Khinoceridae,  up  to  the  present  day,  shows  more 
variability  of  the  incisors  and  canines  than  any 
other  group.  The  dental  formula  of  the  Acerathe- 

2*0*7 
rium  is ~.     Also  by  possessing  four  toes  on 

the  fore-limbs  it  stood  closest  to  its  five-toed  an- 
cestors. Aceratherium  is  followed  upwards  by  the 
true  rhinoceros  with  enlarged  nasal  bones  capable 
of  supporting  heavy  horns.  In  several  of  the 
Diluvial  species — above  all,  in  Rhinoceros  ticho- 
rhinus,1  which  ranged  across  Central  Europe  as  far 
as  the  Asiatic  Polar  Ocean — the  otherwise  gristly 

1  A  rhinoceros,  with  a  bony  partition  between  the  nostrils, 
lived  in  Europe  with  the  mammoth  up  to  the  period  of  Man,  and 
its  fossil  remains,  like  those  of  its  contemporary,  helped  our  fore- 
fathers in  their  conception  of  giants  and  dragons.  On  the  market 
place  in  Klagenfurt  is  a  very  old  stone  image  of  a  dragon,  the 
head  of  which  has  most  unmistakably  been  modelled  from  the 
skull  of  Rhinoceros  tichorhinus. 


196  THE  MAMMALIA. 

partition  between  the  nostrils  became  a  firm  bony 
support  for  the  horn,  an  ossification,  which  is  not 
unfrequently  met  with  in  the  tapir,  as  was  shown 
on  Fig.  31. 

America,  too,  had  its  family  of  Ehinoceroses, 
which  seem  to  have  branched  off  from  the  Middle 
Eocene  Tapiridse,  and  comes  forward  distinctly  in 
the  Upper  Miocene  as  A ceratherium.  Forms  similar 
to  it  are  found  in  the  Pliocene,  but  did  not  leave 
any  descendants  to  the  following  period.  The 
causes  of  its  extinction  in  the  New  World  are  not 
clear.  But  the  reason  of  the  dying  out  of  the 
Diluvial  species  in  the  Old  World,  or  its  withdrawal 
from  the  temperate  zones  to  tropical  regions,  seems 
to  be  pretty  obvious.  For  even  though  individual 
forms — such  as  the  rhinoceros  with  the  bony  par- 
tition between  the  nostrils — were,  like  the  mam- 
moth, able  to  endure  a  rougher  climate,  still  they 
were  not  able  to  face  the  coming  of  the  Glacial 
period.  What  prevented  them  withdrawing  before 
it  we  certainly  do  not  know ;  still  we  may,  at  all 
events,  look  upon  them  as  having  been  the  victims 
of  climatic  changes.  Others,  which  were  able  to 
avail  themselves  of  the  land  bridges  for  with- 
drawing southwards,  survived. 

An  animal  of  the  rhinoceros  type,  which  was 


THE  TAPIR  AND  RHINOCEROS. 


197 


perhaps  a  contemporary  of  Man,  and  one  of  the 
most  gigantic  phenomena  of  the  primeval  world,  is 
the  Elasmotherium.  It  likewise  possessed  a  bony 
partition  between  the  nostrils,  and  was  armed  with 
an  immense  horn,  as  is  proved  by  the  rough  and 
huge  elevation  on  its  forehead.  Its  skull  is  over 
three  feet  in  length.  The  form  of  the  molars,  with 
elaborately  folded  plates  of  enamel,  is  another 


FIG.  33. — Skull  of  the  Elasmotherium.    One-twelfth  nat.  size. 
After  Brandt. 


peculiarity.  This  giant  of  the  Diluvial  period  was 
also  unable  to  preserve  its  existence.  The  few 
remains — among  which  is  an  almost  complete 
skull — have  scarcely  been  found  anywhere  except 
in  the  southern  basin  of  the  Volga. 

The  size  of  the  present  animals  of  the  Rhinoceros 
species,  and  of  most  of  the  primary  species,  will 
seem  less  striking  if  we  take  into  consideration  the 


198  THE  MAMMALIA. 

smaller  species  of  bygone  days,  for  instance,  the 
Rhinoceros  minutus. 

Before  passing  on  to  the  most  docile  and 
important  group  of  the  Odd-hoofed  animals,  the 
horses,  let  us  first  turn  our  attention  to  a  few  of 
the  American  forms,  which  are  distinguished  partly 
by  their  size  and  partly  by  the,  in  most  cases,  very 
unusual  form  of  their  skull ;  in  the  struggle  for  exist- 
ence these  animals,  however,  neither  changed  nor 
left  descendants  which  adapted  themselves  to  cir- 
cumstances. Their  existence  reminds  us  of  the 
Elasmotherium,  inasmuch  as  they  neither  explain 
the  present  (hence  in  reality  stand  apart  from  our 
subject  here),  nor  do  they  awaken  in  us  other  ideas 
for  understanding  the  organic  world ;  but  they 
bear  witness  to  the  incredible  exuberance,  we  may 
almost  say  the  capriciousness,  of  organic  produc- 
tivity during  the  Late  Tertiary  and  Diluvial  periods 
while  the  animals  were  becoming  extinct,  and 
which  periods  were  followed  by  our  Present  age, 
with  a  certain  stability  of  the  inorganic  and 
organic  worlds.  In  this  stability  of  forms,  moreover, 
we  see  one  of  the  preliminary  conditions  of  the 
morphological  and  social  development  of  mankind. 

The  lowest  strata  to  the  east  of  the  Kocky 
Mountains  contain  the  remains  of  the  Brontotherida, 


THE  TAPIR  AND   RHINOCEROS. 


199 


gigantic  animals,  whose  bodies  exceeded  that  of  the 
elephant  in  bulk,  but  they  had  shorter  limbs  with 


FIG.  34. 

A.  Skull  of  Brontotherium  ingens.    One-tenth  nat.  size,     n,  Nasal  bone ; 

»',  mid   jawbone ;    m,  upper  jaw ;  j,    cheek  bone ;  /,  frontal  bone ; 
p,  parietal  bone  ;  e,  condyle. 

B.  The  same  looked  at  from  above,  with  the  brain  given  in  outline.    After 

Marsh. 


four  toes  on  the  front  feet  and  three  behind.     The 
skull  (Fig.  34),  which  is  elongated  after  the  ma.nner 


200  THE  MAMMALIA. 

of  the  Bhinoceros  species,  shows  a  pair  of  bony 
protuberances  (the  supports  for  mighty  horns)  on 
the  upper  jaw,  in  front  of  the  eye-cavities,  and  prob- 
ably the  nasal  bones  and  the  intermediate  space 
between  the  horns  permitted  the  addition  of  a 
proboscis. 

Both  in  the  case  of  Brontotherium  as  well  as 
in  some  members  of  the  family  of  the  gigantic 
Dinocerata,  to  be  spoken  of  presently,  the  relative 
size  of  the  brain  to  the  skull  is  known  from  fossil 
impressions.  According  to  these  the  size  of  the 
actual  brain  substance  must  have  been  extremely 
small  (Fig.  34,  B.).  Its  extent  reminds  one  of  the 
relative  proportions  of  the  reptile  brain,  and  points 
to  an  incongruity  which  must  certainly  have  had 
its  effect  upon  the  dying  out  of  this  and  of  similar 
species.  It  was  in  this  manner  that  all  the  huge 
reptiles  of  the  middle  geological  periods  became 
extinct,  especially  as  land  animals.  The  few  huge 
but  small-brained  reptiles  of  the  present  day,  such  as 
the  crocodiles,  clearly  owe  their  existence  to  the  fact 
that  they  have  continued  to  live  in  water,  also  to 
their  marked  stability.  A  transition  to  life  on  land 
would  lead  to  their  extinction. 

From  the  circumstance  that  one  of  the  more 
recent  strata  of  Oregon  contains  the  remains  of  a 


THE  EQUIM),  OR  HORSES.  201 

perhaps  kindred  genus,  the  Chalicotherium — which 
is  discovered  also  in  Western  America,  in  China, 
India,  Greece,  Germany,  and  France — Marsh  con- 
cludes that  the  places  where  these  remains  were 
found  were  the  stages  by  which,  in  this  and  other 
cases,  the  so-called  *  Old  World '  received  its  animal 
forms. 

2.   THE   EQUID^E,   OE   HORSES. 

On  Fig.  35  we  have  a  drawing,  made  by  Owen  in 
1857,  to  explain  to  his  audience  the  derivation  of  the 
one-hoofed  animal  from  its  three-hoofed  ancestor,  a 
drawing  which  has  been  made  use  of  countless  times 
since  then  by  recent  writers.  The  three-hoofed 
animal  is  the  Palceotherium  medius  discovered  by 
Cuvier  ;  in  outward  appearance  the  foot  is  precisely 
like  that  of  the  tapir,  but  possesses  four  toes  on 
its  fore-foot,  and  thus  represents  an  earlier  form. 
The  Palseotheridse  are  essentially  Eocene ;  to  judge 
from  their  teeth,  they  obtained  their  food  like  the 
tapirs,  and  (with  a  numerous  kindred)  inhabited 
the  marshy  forests  which  had  originated  with  the 
upheaval  of  the  weird  depths  of  the  Jura  and  Chalk 
oceans.  They,  too,  had  found  their  way  to 
Southern  America.  It  is,  we  know,  perfectly  use- 
less, at  the  present  state  of  our  geological  know- 
ledge, to  endeavour  to  determine  by  means  of 
19 


202 


THE  MAMMALIA. 


which  land-bridges  this  migration  took  place  ;  all 
that  can  be  done  meanwhile,  is  to  trace  the  line 
of  the  descendants  of  the  Palseotheridae,  which,  it 
seems,  soon  came  to  an  end  in  South  America,  but 
became  very  numerously  and  continuously  de- 


tnt 


FIG.  35. — Palaeotherium.     Hipparion.     Horse  (after  Owen). 
p,  First  premolar  ;  m,  first  molar. 

veloped  in  North  America ;  and  in  tracing  this  line 
we  must  do  so  independently  of  those  branches 
which  run  parallel  with  them  in  Europe  and  Asia. 
Palaeotherium  is  a  distinctly  three-hoofed  animal. 
Certainly  the  middle  toe  is  somewhat  larger  than 


THE  EQUIPS,  OR  HORSES.  203 

the  two  side  toes,  which,  although  shortened  a 
little,  and  accordingly  somewhat  more  perpen- 
dicular, yet  fully  touch  the  ground,  and  take 
their  share  in  the  work  as  bearers  of  the  weight 
of  the  body.  Now  in  the  genera  which  gradually 
arose  in  the  course  of  time — Palaoiheriwm,  Anchi- 
therium,  Hipparion,  and  Horse — we  can  trace  how 
the  two  side  toes,  n  and  iv,  were  more  and  more 
withdrawn  from  the  ground,  and  became  rudi- 
mentary, whereas  the  middle  toe  increased  in  size, 
stretched  out,  and  finally  became  that  of  the  Horse, 
the  incomparable  runner  and  fellow- worker  of  man. 
Owen  looks  upon  this  as  a  providential  transforma- 
tion designed  for  the  benefit  of  mankind ;  we  look 
upon  it  as  an  adaptation  to  the  formation  of  the 
ground,  to  the  incoming  of  plains,  which  originated 
during  the  Tertiary  period.  Thus  in  Anchitherium 
aurelianense  (Fig.  36),  which  is  still  met  with  even  in 
the  Eocene,  the  tips  of  the  outer  toes  are  scarcely 
withdrawn  from  the  ground,  hence  might  still  have 
been  of  use  to  the  animal  in  walking  through  a  less 
firm  soil. 

The  Hipparion  also,  from  the  Middle  Tertiary, 
possesses  the  lateral  toes  (Fig.  85),  but  these  are  only 
rudiments  of  the  original  toes.  They  have  become 
wholly  useless,  and  in  accordance  with  this  inaction 


204 


THE  MAMMALIA. 


the  bones  of  the  middle  foot 
have  also  become  shortened,  and 
are  on  the  way  of  becoming 
rudimentary.  In  Hipparion  the 
adaptation  of  an  animal  once 
accustomed  to  marshy  ground, 
to  one  which  lived  on  firmer 
ground  with  extensive  meadow 
lands  has  become  completed; 
we  have,  in  fact,  the  transforma- 
tion from  a  slowly-moving  into 
a  swift  animal.  It  ranged  from 
Central  Europe  as  far  as  Central 
Asia,  and  in  both  countries  lived 
in  enormous  herds,  as  we  learn 
from  Gaudry's  graphic  picture  of 
the  Miocene  uplands  of  Pikermi. 
The  transition  from  Hip- 
parion to  the  Horse  is  a  very 
natural  one.  The  two  side  toes 
— which  are  no  longer  of  use  to 
the  organism,  and 
yet  had  to  be 


Fia.  36.-  Left  hind-foot 
of  the  Anchitherium. 
One-half  nat.  size. 
After  Kowalewsky. 


THE  EQUID^E,   OR  HORSES.  205 

nourished — have  been  eliminated  as  ballast.  They 
are  not  yet  quite  cast  off.  The  metatarsals,  or 
so-called  '  splint  bones,'  are  still  attached  to  the 
middle  toe.  The  horse  of  the  future  will  certainly 
have  cast  off  these  rudiments,  even  though  it  may 
take  a  few  millions  of  years  to  accomplish  this, 
owing  to  the  extraordinary  perseverance  with  which 
organisms  drag  about  with  them  these  useless  in- 
heritances. The  Hipparion  has  not  even  yet 
wholly  disappeared  from  the  scenes  of  life. 

Now  and  again  horses  have  been  met  with,  with 
more  than  one  toe,  which  must  not  rashly  be 
considered  as  a  malformation  ;  it  is  simply  a  proof 
of  that  repetition  of  or  reversion  to  the  original  form 
which  in  scientific  language  is  called  atavism. 
This  kind  of  Hipparion-horse,  which  is  looked  upon 
by  the  common  run  of  people  as  a  curiosity  and 
monstrosity,  has,  as  Siebold1  has  shown,  been 
repeatedly  exhibited  at  horse-markets.  The  fol- 
lowing is  a  description  of  an  animal  of  this  kind 
given  by  Frank,  Principal  of  the  Veterinary  College 
of  Surgery  at  Munich :  *  The  so-called  splint  bones 
(the  metacarpals  and  metatarsals  of  the  second 
and  fifth  toes)  are  not  reduced  to  the  same  extent. 
On  the  fore-foot  the  mediale  (M  c  2)  is  the  least 

1  Siebold,  Hipparion  auf  JahrmtirMen.     Miinchen,  1881. 


206  THE  MAMMALIA. 

reduced,  on  the  hind-foot  the  lateral  (M  c  4)  is  the 
least  reduced,  as  even  Hensel  pointed  out.  Now 
cases  of  atavism  are  not  unfrequently  met  with  in 
the  horse,  where  the  medial  splint  bone  on  the 
fore- foot  has  a  digit  more  or  less  distinctly  de- 
veloped. And  as  the  hoof  of  this  second  digit  never 
touches  the  ground,  and,  accordingly,  is  not  worn 
off  in  any  way,  the  horn-substance  becomes  long 
and  irregular,  precisely  as  in  the  case  of  the  lateral 
toes  (the  second  and  fifth)  in  old  cows.  Atavisms 
of  this  kind  on  the  hind- foot  are  of  extremely  rare 
occurrence. 

*  When  it  was  said  above  that  the  horse  no  longer 
shows  any  trace  of  rudimentary  toes,  this  is  not 
altogether  correct ;  the  rudimentary  hoofs  do  still 
exist.  Thus  the  so-called  "  chestnut,"  a  flat  horny 
wart  on  the  skin  above  the  carpus,  seems  to  corre- 
spond to  the  hoof  of  the  lost  thumb ;  at  all 
events,  I  found  it  in  cases  where  a  second  digit 
existed.  Another  formation  that  must  be  included 
here,  is  the  so-called  "  spur."  This  spur  is  a  small 
cylindrical  horny  substance,  which  in  our  present 
horse  is  concealed  by  the  hairy  tufts  of  the  fetlock. 
It  seems  to  represent  the  coalesced  horn- shoe  of 
the  rudimentary  second  and  fourth  toe  of  the 
horse. 


THE  EQUID^E,  OE  HOESES.  207 

4  During  the  sixth  decade  of  the  present  century, 
there  was  exhibited  in  Munich  a  horse  under  the 
name  of  a  "  stag-horse,"  which  had  veritable  hip- 
parion  feet.  The  splint  bones  of  the  four  extrem- 
ities had  digits,  that  is,  toes.  The  so-called 
"  chestnuts  "  existed  on  all  the  four  limbs,  and  were 
strongly  developed,  whereas  all  the  four  "  spurs  " 
were  wholly  wanting.1  On  the  fore-feet  the  medial 
side-hoof  (second  digit)  was  most  fully  developed, 
on  the  hind-feet  it  was  the  lateral  or  fourth  toe.  As 
the  side-hoofs  of  all  the  extremities  did  not  reach 
the  ground,  and  hence  were  not  worn,  they  had 
grown  to  a  considerable  length,  and  were  bent  like 
horns.  Such  cases  are  of  great  rarity ;  still  they 
had  been  observed  even  in  earlier  times.  The 
famous  Bucephalus  of  Alexander  the  Great  is  said 
to  have  been  an  animal  of  this  kind.  Moreover, 
the  atavism  is  said  in  some  instances  to  have  been 
transmitted  to  the  offspring,  which  of  course  is  very 
probable.  It  is  more  than  probable  that  from  a 
single  animal  of  this  description  a  breed  of  Hip- 
parion-horses  might  be  reared.  There  would, 

1  This  observation  would  certainly  support  the  opinion,  which 
we  are  inclined  to  doubt,  that  the  '  chestnuts  '  and  '  spurs '  were 
rudiments  of  the  first,  second,  and  fifth  hoofs.  If,  nevertheless, 
I  hold  to  my  doubt,  at  all  events  as  regards  the  atavism  of  the 
thumb,  I  do  so  because  it  would  be  a  unique  phenomenon. 


208  THE  MAMMALIA. 

however,  be  absolutely  nothing  to  be  gained  by 
such  reactionary  measures.' 

The  same  indications  of  the  transformation 
from  Palseotherium  to  our  present  Horse — in  an 
uninterrupted  line  from  the  Eocene  to  the  present 
— are  manifested  by  the  teeth.  In  connection 
with  this  point  we  must  first  of  all  mention 
Kiitimeyer's  classic  studies  on  this  question,1  which 
have  Jbeen  admirably  supplemented  by  Forsyth- 
Major.  Owen  had  already  recognised  the  change 
in  the  formation  of  the  jaw  that  accompanied  the 
transformation  of  the  organs  of  locomotion.  The 
teeth  of  the  Palseotheridse,  which  show  less  com- 
plicated folds  of  enamel,  and  are  adapted  for 
crushing  juicy  plants,  gradually  change  into  the 
pillar-shaped  molars  of  the  horse,  which,  owing  to 
their  strength  and  the  foldings  of  enamel,  are 
suitable  both  for  grinding  corn  and  for  chopping 
gritty  grasses.  The  principal  parts  of  the  crowns 
are  given  on  the  accompanying  drawing  (Fig.  37). 
Even  from  Owen's  illustration  it  is  evident  how  the 
complicated  enamel  lines  of  the  horse's  tooth 
originated  from  the  simple  tracings  on  the  tooth 
of  the  Eocene  animal.  The  much  more  careful 

1  Kiitimeyer,    Beitrage  zur  Kenntniss  der  fossilen  Pferde, 
1863. 


THE  EQUID^E,   OR  HORSES. 


209 


comparisons  of  recent  times  have  shown  us  these 
changes  down  to  the  minutest  detail ;  and  from  the 
geological  series,  which  is  being  made  more  com- 
plete year  by  year,  the  complex  formation  of  the 
horse's  molars  becomes  perfectly  intelligible  from 
the  outlines  on  those  of  the  Palseotherium.  Kiiti- 


FIG.  37.— Right  Upper- jaw  Molar  of  the  Horse. 

a,  i,  »,  h.  Outside,  inside,  front,  back ;  M,  m,  front,  back  crescent ;  P,  p,  larger 
and  smaller  inner  pillar  ;  F,f,  inner  main-  and  side-fold.    After  Branco. 

meyer  further  gives  special  proofs  that  the  species 
in  question  transmitted  the  relative  peculiarities  of 
their  molars  to  the  milk-teeth  of  their  offspring 
and  descendants,  whereas  the  descendants  trans- 
mitted the  new  inheritance  specially  to  the  molar 
teeth. 


210  THE  MAMMALIA. 

It  is  only  in  its  historical  connection  that  the 
peculiarity  of  the  horse's  dentition  acquires  a 
peculiarly  significant  interest,  and — as  in  the  case 
of  the  three-toed  foot — when  viewed  apart  from  the 
historical  course  of  its  development,  seems  simply 
an  incomprehensible  peculiarity,  of  no  importance 
either  to  the  horse  itself  or  to  the  horse  fancier, 
Palseotherium,  Anchitherium,  and  Hipparion  pos- 
sess, when  full  grown,  seven  cheek-teeth  above  and 

t  q 

below  on  both  sides  of  the  jaw,  p  -,  m  - .  On  the 
other  hand  the  normal  formula  in  the  horse's  den- 

q  q 

tition  is  p  -,  m  -;  it  changes  only  three   of  its 
o  o 

milk-teeth,  and  gets  three  other  molars.  Now  it 
has  long  since  been  known  to  breeders  and  veterinary 
surgeons  that,  pretty  frequently,  the  horse's  row 
of  cheek-teeth  begins  with  one  stump  too  many, 
the  so-called  *  wolfs  tooth'  (on  Owen's  drawing 
marked  by  the  letter  p).  This  most  perfectly  ex- 
presses the  fact  that  it  occupies  the  place  where, 
in  Palaeotherium  among  others,  we  have  the  first 
premolar.  When  it  appears  in  the  horse,  however, 
the  '  wolf  s-tooth '  is  not  deciduous.  It  is  most 
obviously  a  tooth  in  the  last  stage  of  disappear- 
ance, an  irregularly  appearing  descendant  from  the 


THE  EQUID^E,  OR  HORSES.  211 

days  of  a  full  dentition,  and  its  disappearance 
probably  stands  in  causal  connection  with  the 
increased  strength  of  the  other  teeth. 

Before  discussing  the  American  line  of  horses, 
let  me  here  quote  W.  Kowalewsky's  opinion  regard- 
ing the  connection  between  the  genera  mentioned 
above ;  his  remarks  are  as  careful  as  they  are  con- 
vincing: *  Nothing  is  further  from  my  intention 
than  to  maintain  that  the  animal  which  we  call 
Palceotherium  medium  directly  produced  an  Anchi- 
therium,  the  latter  an  Hipparion,  and  so  on.  But 
among  the  number  of  individuals  which  we  call 
Palaeotheridae,  there  must  always  have  been  some 
forms  which  would  incline  more  towards  the  Anchi- 
therium  than  the  others.  In  the  same  way  I  have 
been  able  to  determine — owing  to  the  large  number 
of  species  I  was  fortunate  enough  to  be  able  to  com- 
pare— that  among  the  Anchitheridae  a  few  still 
remained  completely  within  the  limits  of  the  species, 
although  they  showed  some  characteristics  by  which 
they  resembled  the  Horse  on  the  one  hand,  and  the 
Palaeotherium  on  the  other.  A  few  trifling  flattenings 
of  the  bones,  certain  peculiarities  of  a  joint  which 
are  met  with  in  some  individuals,  are  not  to  be  found 
in  others.  Without  doubt  there  was  at  one  time  a 
transition  between  two  individuals  which  resembled 


212  THE  MAMMALIA. 

each  other  most;  but  to  expect,  as  is  generally 
asked  by  those  who  believe  in  the  invariability  of 
species,  that  we  should  be  able  to  show  the  last 
Palaeotherium,  and  his  descendant  the  first  Anchi- 
therium,  is  to  demand  an  impossibility.  An  origin- 
ally normal  characteristic  sometimes  begins  not  to 
occur,  then  it  becomes  unimportant,  i.e.  is  found 
wanting  as  often  as  it  occurs,  then  it  appears  rarely, 
and  finally  disappears  completely.  Thus,  for  in- 
stance, the  small  front  premolar  of  Palaeotherium 
is  smaller  still  in  Anchitherium,  but  still  occurs 
regularly ;  in  the  Hipparion  it  is  met  with  as  often 
as  it  is  found  missing,  and  in  our  present  Horses 
it  is  extremely  rare  (as  the  "  wolfs  tooth  ").'  This 
very  careful  comparison  of  the  differences  in  the 
dentition  has  been  further  worked  out  by  Kowa- 
lewsky.1 

We  have  now  again  to  turn  to  America,  to  the 
well-known  fields  of  discovery  to  the  right  and  left 
of  the  Rocky  Mountains,  where  to  all  appearances 
a  group  of  Odd-hoofed  animals  lies  buried,  much 
more  numerous  in  members  than  the  group  in  the 
Old  World,  showing  no  gaps,  and  terminating  with 
the  horse.  Compare  the  table  on  page  190.  The 

1  W.  Kowalewsky,  '  Sur  1'Anchitherium  Aurelianense  Cuv.,1 
M6m.  de  VAcadtonie  imp.  de  St.  PUersbourg,  1873. 


THE  EQUID.E,  OB  HOESES. 


213 


line  begins  in  the  Early  Eocene  with  the  Eohippus 
of  the  size  of  a  fox,  which  possessed,  in  addition  to 
the  four  well-developed  toes  of  the  fore-foot,  the 
remnants  of  a  fifth.  According  to  a  remark  of 
Marsh's,  this  animal,  in  foot  and  dentition,  al- 
ready shows  unmistakably  that  with  it  commenced 
the  branching  off  of  the  progenitors  of  the  horse 

d 


JH  m  mm 

Fro.  38.— Foot  of  the  Fossil  Horses  of  North  America, 
a,  Orohippus ;  6,  Mesohippus  ;  c,  Miohippus ;  d,  Protohippus  ;  e,  Equus, 

from  the  other  Odd-hoofed  animals :  '  in  the  next 
higher  division  of  the  Eocene,  another  genus 
(Orohippus,  Fig.  38)  makes  its  appearance,  replacing 
Eohippus,  and  showing  a  greater  though  still  dis- 
tant resemblance  to  the  equine  type.  The  rudi- 
mentary first  digit  of  the  fore-foot  has  disappeared, 
and  the  last  premolar  has  gone  over  to  the  molar 
20 


214  TEE  MAMMALIA. 

series.  Orohippus  was  but  little  larger  than 
Eohippus,  and  in  most  other  respects  very  similar. 

'  Near  the  base  of  the  Miocene  we  find  a  third 
closely  allied  genus  (Mesohippus),  which  is  about  as 
large  as  a  sheep  and  one  stage  nearer  the  horse. 
There  are  only  three  toes  and  a  rudimentary  splint 
bone  on  the  fore-feet  and  three  toes  behind.  Two 
of  the  premolar  teeth  are  quite  like  molars.  The 
ulna  is  no  longer  distinct,  or  the  fibula  either,  and 
other  characters  show  clearly  that  the  transition  is 
advancing.  In  the  Upper  Miocene  Mesohippus  is 
not  found,  but  in  its  place  a  fourth  form  (Mio- 
hippus)  continues  the  line.  The  genus  stands 
close  to  the  Anchitherium  of  Europe,  but  presents 
several  important  differences.  The  three  toes  in 
each  foot  are  more  nearly  of  a  size,  and  a  rudi- 
ment of  the  fifth  metacarpal  bone  (of  the  second 
series)  is  retained.  All  the  known  species  of  this 
genus  are  larger  than  those  of  Mesohippus,  and 
none  pass  above  the  Miocene. 

*  The  genus  Protohippus  of  the  Lower  Pliocene  is 
still  more  equine,  and  some  of  its  species  equalled 
the  ass  in  size.  There  are  still  three  toes  on  each 
foot,  but  only  the  middle  one,  corresponding  to  the 
single  toe  of  the  horse,  comes  to  the  ground.  This 
genus  resembles  most  nearly  the  Hipparion  of 


THE  EQUIDJE,  OE  HOESES.  215 

Europe.  In  the  Pliocene  we  have  the  last  stage  of 
the  series  before  reaching  the  horse,  in  the  genus 
Pliohippus,  which  has  lost  the  small  hooflets  and 
in  other  respects  is  very  equine.  Only  in  the 
Upper  Pliocene  does  the  true  Equus  appear  and 
completes  the  genealogy  of  the  horse,  which  in  the 
Post-Tertiary  roamed  over  the  whole  of  North  and 
South  America,  and  soon  after  became  extinct. 
This  occurred  long  before  the  discovery  of  the 
continent  by  Europeans,  and  no  satisfactory  reason 
for  its  extinction  has  yet  been  given.' l 

So  far  Marsh,  and,  owing  to  the  quantity  of  his 
discoveries,  he  proclaims  the  horse,  above  all  the 
other  hoofed  animals,  to  be  clearly  a  native  of 
America.  That  the  European  line  discussed  above 
is  more  incomplete  is  very  evident ;  however,  it  must 
be  assumed  that  with  further  discoveries  the  differ- 
ence will  be  equalised.  And,  indeed,  an  important 
beginning  has  already  been  made  during  the  last 
few  years.  The  gap  between  Hipparion  and  Equus, 
which  clearly  existed,  and  was  filled  up  in  the  Ame- 
rican line  by  Pliohippus,  no  longer  exists  in  the  Euro- 
pean series  either.  For  Forsyth-Major 2  has  pointed 

1  Marsh,  The  Introduction  and  Succession  of  Vertebrate  Life 
in  America  (1877). 

2  Forsyth-Major,    '  Bivista     scientifica     industriale,    187G,1 
Kosmos,  ii. 


216  THE  MAMMALIA. 

out  that  the  races  from  the  Quaternary  period  of 
Upper  Italy,  classed  together  as  Equus  stenonis, 
include  all  the  required  intermediate  stages  between 
Hipparion  and  our  present  Equus  caballus.  It  is 
of  the  utmost  interest  to  be  able  to  prove  that  in 
Equus  stenonis  the  reduction  of  the  side  meta- 
tarsals  preceded  that  of  the  tarsals  :  for  while  the 
metatarsals  do  not  differ  from  those  of  our  present 
horse,  the  tarsals  show  all  the  intermediate  stages 
between  Hipparion  and  Equus  caballus  ;  they  have 
not  yet  had  a  sufficient  length  of  time  to  accom- 
plish the  complete  change  which  renders  the  foot 
of  our  horse  so  eminently  more  suited  to  the 
activity  of  the  one-hoofed  animal  than  was  the 
Equus  stenonis.  In  fact,  it  may  be  affirmed  that 
in  the  case  of  the  Diluvial  horses,  the  splint  bone 
(i.e.  the  rudiments  of  the  metatarsals  n  and  iv) 
had  not  yet  coalesced  with  the  mid-foot,  which 
coalescing  of  the  bones  occurs  in  our  present  horse 
with  its  seventh  or  eighth  year.1 

1  Nehring  remarks,  on  the  other  hand,  that  in  our  present 
horse,  the  splint  bones  do  not  coalesce  nearly  as  often  as  is  sup- 
posed, and  that,  for  instance,  among  the  skeletons  in  the  Berlin 
collection,  the  coalescing  is  the  exception,  the  non-coalescing  the 
rule.  That,  therefore,  the  supposed  difference  between  the  Dilu- 
vial and  the  present  horse  is  not  an  essential  one,  and  that  it 
need  only  be  admitted  that  the  coalescing  of  the  splint  bones 
occurs  more  frequently  in  the  domestic  horses  .of  the  present 


THE  EQUID.E,  OR  HOUSES.  217 

That  the  two  groups,  the  European  and  the 
American,  run  parallel,  perhaps  without  any  inter- 
course during  the  longest  of  the  Mid-tertiary 
periods,  must  not  only  be  admitted  as  probahle, 
but  be  granted  as  possible.  The  probable  coloni- 
sation of  America  by  the  original  inhabitants  of 
Asia  took  place  before  they  had  learned  to  make 
use  of  the  horse  as  a  domestic  animal.  In 
America  the  Horse  no  longer  existed  then.  It 
may  be  that  the  long-continued  ice-formations 
of  the  Diluvium  had  forced  it  to  leave  the  high- 
lying  plains  to  which  it  had  been  accustomed, 
and  driven  it  to  regions  where  it  succumbed  in 
the  struggle  for  existence.  The  Spaniards  re- 
introduced  the  horse  to  the  New  World,  and  now  it 
there  also  fulfils  its  mission  as  a  companion  to 
man — if  we  may  for  once  use  a  teleological  ex- 
pression. In  addition  to  all  this,  however,  it  must 
also  be  stated  that  the  American  members  of  the 
genus  Horse  have  never  advanced  as  close  to  our 
present  horse  as  the  Diluvial  members  of  the  Euro- 
pean family ;  hence,  that  the  true  horse  of  our 

than  in  the  Diluvial  horses.  Now,  as  Nehring,  among  other 
things,  proves  that  the  splint  bones  of  the  Diluvial  horse,  of 
Westeregel,  are  considerably  larger  and  longer  than  they  are 
usually  found  in  the  domestic  horse,  the  circumstances  we  en- 
deavoured to  prove  above  remain  essentially  the  same. 


218  THE  MAMMALIA, 

day — Equus  caballus— never  existed  in  America 
before  its  importation.  Branco1  has  lately  pub- 
lished a  very  remarkable  treatise  on  this  subject. 
He  has  shown  that  in  the  Equus  andium — which 
lies  buried  in  the  volcanic  tufa  of  Ecuador,  and  is 
of  the  same  age  as  the  Diluvial  Pampas  horses  and 
the  species  found  in  the  caves  of  Brazil — the  eye 
is  placed  considerably  deeper,  whereas  in  the  Equus 
caballus  it  has  moved  considerably  farther  back. 
Here,  again,  it  is  our  grand  Goethe — a  naturalist 
not  nearly  often  enough  quoted,  in  spite  of  what 
an  eminent  Berlin  orator  may  say — who  sixty 
years  ago  pointed  out  this  ideal  character  of  the 
horse  from  an  artistico-scientific  point  of  view,  and 
thus  anticipated  the  wearisome  labours  of  palaeon- 
tology. Goethe's  words  are2 :  *  In  the  horse's  head 
of  the  Elgin  Marbles  (of  the  Parthenon),  one  of  the 
most  splendid  relics  of  the  grandest  period  in  art, 
the  eyes  stand  out  freely  and  are  placed  near  the 
ears,  whereby  both  senses,  sight  and  hearing,  seem 
to  act  together  directly,  and  the  sublime  creature 
is  enabled  to  hear  as  well  as  to  see  what  is  happen- 
ing behind  it.  It  looks  so  majostic  and  spirituel, 

1  Branco,  Die  fossile  Saugethier -fauna  von  Punin  und  Ecua- 
dor, von  Eeiss  und  Branca.    Berlin,  1883. 

2  Goethe,     Ueber    die    Anforderungen    an    naturhistorische 
Zeichnungen  (1823). 


THE  EQUID.E,   OE  HORSES.  219 

almost  as  if  it  had  been  formed  contrary  to  nature, 
and  yet  the  artist  has,  in  reality,  given  us  a  pri- 
meval horse,  whether  he  saw  it  with  his  own  eyes 
or  conceived  it  in  his  mind ;  to  us,  at  all  events, 
the  animal  seems  depicted  in  the  spirit  of  the 
highest  form  of  poetry  and  reality.' 

The  horse,  in  all  its  various  forms  of  develop- 
ment, from  the  dwarfish  pony  to  the  Percheron 
and  the  huge  English  cart  horse,  has  been  regarded 
as  a  single  species  ever  since  it  was  found  in  the 
service  of  man.  We  talk  only  of  different  races 
of  Equus  cdballm.  The  taming  and  breeding  of 
horses  may  be  said  certainly  not  to  have  taken 
place  for  thousands  of  years  after  the  time  when 
man  first  came  into  contact  with  the  animal.  The"") 
period  during  which  prehistoric  Man,  in  Europe, 
fed  chiefly  upon  horse  flesh  is  that  which  has  also 
been  called  the  Eeindeer  period,  owing  to  the  wide 
distribution  of  that  animal.  This  division  of  time 
follows  the  period  of  the  fullest  development  of  the 
mammoth,  and  was  in  many  localities— e.g.  in 
Central  France — extremely  favourable  for  the  in- 
crease of  the  genus  Horse,  in  spite  of  an  evidently 
rough  climate.  Nowhere  in  the  world  are  such" 
accumulations  of  remains  found  as  near  Solutre  in 
the  neighbourhood  of  Macon  to  the  north  of  Lyons.  ! 


THE  MAMMALIA. 


The  lower  stratum  of  this  remarkable  deposit  con- 
tains a  whole  fauna  of  larger  and  smaller  mam- 
mals— mammoth,  cave  tiger,  lynx,  cave  bear,  brown 
bear,  cave  hyena,  wolf,  fox,  polecat,  marten,  bad- 
ger, Canadian  deer,  primeval  ox,  horse,  hare,  and 
saiga-antelope.  All  the  bones  are  broken  and 
mixed  up  together ;  and  the  rude  flint  implements 
likewise  found  there,  also  point  to  the  fact  that  the 
grass-eaters  fell  victims  not  only  to  the  teeth  of  the 
beasts  of  prey,  but  to  the  hand  of  huntsmen  as 
well.  In  the  upper  strata  the  mammoth  and  his 
huge  flesh-eating  contemporaries  disappear  from 
the  scenes.  Primeval  Man  entered  the  Keindeer 
period  from  the  Mammoth  period,  and  thereupon 


horses  were  slain  by  the  thousand. 


V' 

The  opinion  which  found  favour  in  France  that 
the  horse  of  Solutre  had  been  tamed  and  domes- 
ticated is  untenable,  as  has  again  lately  been 
pointed  out  by  Pietrement,  who  has  carefully  con- 
sidered the  question  in  all  its  bearings.1  Never- 
theless, the  horse  from  Solutre  is  of  great  interest, 
as  we  most  probably  have  in  it  one  of  the  races 
which  subsequently  became  domesticated,  and  which 
left  descendants  that  probably  still  exist.  The  pieces 

1  Pietrement,  Les  chevaux  dans  les  temps  prehistorigues  et 
historiques.    Paris,  1883. 


THE  EQUID^E,  OR  HOUSES.  221 

of  skeletons  found  at  Solutre  point  to  the  so- 
called  Ardennes  horse,  one  of  the  long-headed  races 
of  the  domestic  horse.  One  feels  tempted  to  look 
round  and  see  whether  there  are  not  other 
horses  that  approach  as  close  to  the  Solutre  branch. 
In  doing  this  we  think,  in  the  first  place,  of  the 
small  horse  that  lives  in  a  semi- wild  state  on  the 
Carmargue,  in  the  delta  of  the  Ehone.  There  also 
exist  in  Alsace  the  last  offshoots  of  an  old  race  of 
this  kind.  In  stature  and  proportions  these  ani- 
mals resemble  large  ponies.  The  head,  in  the 
specimens  which  seem  most  purely  to  represent 
the  race,  is  large  and  ugly,  but  the  body,  in  spite  of 
the  want  of  actual  care,  is  well  formed ;  the  limbs 
very  powerful.  The  animals,  which  are  good- 
natured  and  easy  to  manage,  perform  extraordinary 
feats  in  the  way  of  drawing  weights.  At  times, 
when  there  is  little  work  doing,  they  are  kept  for 
weeks  in  the  meadows  to  the  east  of  Schlett-stadt, 
and  are  met  with,  in  fact,  in  other  districts  besides 
Schlett-stadt  as  far  as  the  Ehine. 

To  throw  proper  light  upon  this  possible  con- 
nection, it  would  be  necessary  to  make  the  most 
careful  examination  and  measurements  of  the 
various  parts  of  the  skeleton,  and  this  has  not  yet 
been  done.  How  this  would  have  to  be  done  has 


222  THE  MAMMALIA. 

been  shown  very  recently  by  the  distinguished 
authority  on  the  Diluvial  mammals  of  Central 
Europe,  Professor  Nehring  of  Berlin,  in  his  ex- 
ceedingly interesting  studies  on  the  fossil  horses  of 
the  German  Diluvial  deposits,  and  their  relation  to 
the  living  horses.1  The  Italian  palaeontologist, 
Forsyth-Major,  had,  somewhat  previously,  in  an 
admirable  manner,  compared  the  Diluvial  horse  in 
Italy  with  the  present  animal.  In  order  to  obtain 
a  good  starting-point  for  an  investigation  of  this 
kind,  it  is  necessary  first  to  understand  a  few  of  the 
principal  species  of  the  domestic  horse.  Of  these 
we  require  only  the  two  groups  in  which,  according 
to  French  investigators,  the  domestic  horse  appears, 
and  into  which,  moreover,  the  eight  races  may  be 
subdivided.  In  the  horses  of  the  principal  Oriental 
race,  the  portion  of  the  skull  covering  the  brain  is 
strongly  developed,  the  facial  part  of  the  head  is 
smaller,  which  circumstance  is  expressed  mainly 
by  the  breadth  of  the  forehead.  The  inner  side  of 
the  crescents  of  the  molars  of  the  upper  jaw 
(Fig.  37)  has  a  covering  of  enamel  with  but  few 
folds;  the  bones  of  the  limbs  are  graceful,  but 
of  a  very  firm  structure.  An  admirable  represen- 

1  Nehring,  Fossile  Pferde  aus  deutschen  Diluvialablagerungen 
und  ihre  Beziehungen  zu  den  lebenden  Pferden.    Berlin,  1884. 


THE  EQUIDJ2,  OB  HORSES.  223 

tative  of  these  qualities  is  found  in  the  Arabian 
horse. 

'  The  Occidental  Horse,'  says  Nehring — following 
Frank  of  Munich,  who  was  the  first  to  distinguish 
this  main  race — '  shows  itself,  as  regards  the  two 
first  mentioned  points,  to  be  the  exact  reverse  of  the 
Oriental  horse ;  for  its  distinguishing  character  is 
the  much  larger  development  of  the  facial  portion 
of  the  skull,  as  compared  with  the  part  covering 
the  brain.  The  skull  seems  to  be  comparatively 
long  and  narrow  with  a  small  breadth  of  forehead. 
The  rims  of  the  eye-cavities  stand  somewhat  for- 
ward. The  enamel  folds  of  the  so-called  crescents 
of  the  molars  of  the  upper  jaw  are  very  complicated. 
The  bones  of  the  limbs  of  the  Occidental  horse  are 
of  a  thick  and  massive  build,  while  in  structure 
they  are  less  substantial  and  hard  than  in  the  case 
of  the  Oriental  horse.' 

To  this  Occidental  race,  in  Germany,  belongs 
our  common-middle-sized  horse,  which  of  late  years 
has  been  more  and  more  set  aside  to  make  room 
for  a  mixed  race ;  for  the  State  and  private  persons 
have  taken  the  breeding  of  horses  into  their  own 
hands  and  introduced  foreign  animals,  more  par- 
ticularly of  the  Oriental  species.  Thus,  for  example, 
during  some  decades,  crossings  from  the  Arabian 


224  THE  MAMMALIA. 

breed,  especially  with  the  famous  stud  at  Graclitz 
near  Torgan,  was  systematically  encouraged  in  the 
districts  on  the  Elbe  in  Saxony. 

The  heavy  horse  of  Central  Germany  has  been 
termed  the  Equus  caballus  germanicus  by  Sanson, 
and  by  Pietrement  after  him.  There  were  only 
uncertain  conjectures  as  to  its  origin,  yet  the 
general  opinion  appeared  to  be  that,  like  all  the 
medium- sized  and  larger  European  races,  it  was  of 
Asiatic  origin,  and  that  it  had  been  tamed  and 
introduced  by  different  nomadic  tribes  in  prehistoric 
times.1  This  question,  which  claims  our  whole 
interest,  for  it  affects  the  history  of  the  noblest  of 
our  domestic  animals,  has  advanced  one  stage  in 
clearness.  Nehring  has  undeniably  proved  that  a 
Diluvial  horse  of  Central  Germany — numerous  re- 
mains of  which  have  been  discovered  at  Westeregeln 

1  *  The  Eoman  authors,  Caesar  in  particular,  distinguish  in 
Gaul  and  Germany  between  a  native  race  of  horses,  which  was 
small  and  unremarkable  although  hardy,  and  between  foreign 
breeds  that  were  larger  and  nobler  in  appearance.  And  many 
other  writers  of  ancient  and  later  times  speak  of  foreign  horses 
in  contradistinction  to  the  native  breeds,  so  that  there  is,  pro- 
bably, no  doubt  that  there  existed  in  those  days,  in  Germany, 
two  races  strikingly  different  in  outer  appearance.  That  the 
small  native  race  must  be  traced  to  the  tamed  wild  horse  of 
Europe,  may  probably  be  considered  as  certain,  so  that  the  only 
remaining  question  is,  of  what  origin  was  that  foreign  horse,  and 
whence  did  it  come  to  us  ?  '— Al.  Ecker. 


THE  EQUID^E,  OR  HORSES.  225 

near  Magdeburg,  and  at  Thiede  in  Brunswick — 
tallies  in  all  characteristic  features  with  the  heavy 
Occidental  horse.  Hence  it  had  not  been  introduced, 
but  had  been  tamed  and  reared  by  our  ancestors 
from  the  wild  race  which  they  found  there.  This 
narrow-browed  animal  lived  also  on  the  Ehine,  in 
the  neighbourhood  of  Eemagen ;  *  in  the  form  of 
its  skull  and  the  rims  round  the  eye-cavities  it 
resembles  our  old  medium-sized  lowland  races.' 

Nehring  sums  up  his  views  regarding  the  Ger- 
man Diluvial  horse  and  its  relation  to  the  present 
tamed  and  wild  races,  in  the  following  passage  of 
general  interest :  '  The  Diluvial  horse  of  our 
country,  like  that  of  the  neighbouring  European 
lands,  was  an  untamed,  wild  animal  which  roamed 
about,  and  seems  to  have  lived  in  especially  large 
numbers  in  the  districts  round  the  Hartz  Moun- 
tains. These  districts,  during  one  distinctly  longer 
division  of  the  Diluvial  period,  possessed  a  vegeta^- 
tion  of  the  steppe  species  and  a  corresponding 
climate.  The  forest  had  become  greatly  reduced 
during  the  Ice  period  (i.e.  the  first  ice  period,  if  we 
are  to  admit  of  there  having  been  two).  On  these 
steppe-like  tracts  wild  horses  lived  in  large  herds, 
together  with  jerboas,  steppe-susliks,  logamys,  hare- 
rats,  numerous  wild  mice,  and  other  characterise 
21  V  ' 


226  THE  MAMMALIA. 

inhabitants  of  the  present  steppes  beyond  the 
Volga.1 

'  Their  existence  was  now  and  again  endangered 
by  a  few  isolated  lions,  also  by  wolves,  whereas 
hyenas  (remains  of  which  are  not  unfrequently 
met  with  at  "Wester egeln)  probably  seized  only  the 
carcases  and  scarcely  ventured  to  attack  the  live 
horses. 

'The  worst  enemy  of  the  Diluvial  horse  was 
man.  We  know  by  numberless  investigations,  that 
the  human  inhabitants  of  Central  and  Western 
Europe  in  those  days  lived  almost  entirely  upon 
the  hunting  of  horses  ;  the  bones  and  teeth — very 
probably  the  skins,  hair,  and  sinews  also — were  made 
use  of  in  a  variety  of  ways.'  Nehring,  whom  we 
have  been  quoting,  goes  on  to  say  how  all  this  was 
done,  what  proofs  we  have  of  the  occasional  visit 
of  nomadic  tribes  to  certain  localities,  and  how  a 
regular  system  of  breeding  arose  gradually  from 
single  attempts,  and  then  adds: 

*  Those  of  my  readers  who  are  accessible  to 
scientific  proofs  will,  I  hope,  find  my  detailed  com- 
parisons sufficient  to  convince  them  that  an  essen- 
tial portion  of  our  so-called  heavy  (common)  horses 
must  be  traced  back  to  the  heavy,  thick-boned 

Diluvial  horse.' 
*s* 

1  Compare  above,  p.  76,  fol. 


THE  PROBOSCID^E,  OR  ELEPHANTS.          227 

The  horse  from  Solutre,  and  the  thick-boned 
animal  of  Central  Germany,  are  two  local  races 
very  nearly  related,  but  yet  distinguishable.  There 
is  another  race  which  has  been  found  most  com- 
plete round  about  Schussenried  in  south-western 
Wiirtemberg ;  it  has  been  described  by  the  eminent 
man  of  science,  Fraas,  who  also  gives  an  account  of 
many  of  the  other  Diluvial  inhabitants  of  that  dis- 
trict. This  horse  is  distinguished  by  its  compara- 
tively broad  forehead  and  by  the  gracefulness  of  its 
limbs,  and  hence  agrees  in  important  points  with 
the  Oriental  domestic  horse.  Now  there  have  been 
discovered  in  many  of  the  prehistoric  deposits  of 
the  Bronze  period,  the  remains  of  a  tamed,  thin- 
boned  horse,  which  has  universally  been  supposed 
to  be  of  Asiatic  origin.  It  cannot  well  be  doubted 
that  this  horse  was  imported  by  the  tribes  that 
overran  Europe  from  the  East;  yet  it  is  equally 
possible  and  probable,  that  a  portion  of  the  slimmer, 
tamed  horses  of  the  Bronze  period  had  been  pro- 
duced through  the  taming  of  the  broad-browed 
Diluvial  horse  of  South  Germany. 

5.    THE    PROBOSCID^B,    OR   ELEPHANTS. 

The  circumstances  of  nutrition  which  determine 
the  general  character  of  the  dentition  and  of  the 


228  THE  MAMMALIA. 

structure  of  the  feet  of  animals,  account  for  the 
fact  that  the  trunked- animals  have  always  been 
classed  with  the  genuine  hoofed  animals  ;  but  any 
attempt  at  a  closer  definition  of  the  older  system, 
with  its  many-hoofed  animals  and  thick-skinned 
animals,  always  led  to  the  isolation  of  the  ele- 
phants. Their  dentition  shows  no  link  whatever 
with  those  of  the  present  animals.  And  in  causal 
connection  with  the  dentition  we  have  the  strange 
shape  of  the  skull,  and  again  connected  with  the 
latter  the  development  of  the  proboscis,  which  in  a 
wonderful  manner  counterbalances  the  weight  and 
awkwardness  of  the  head  and  neck.  Probosces  are 
met  with  in  other  mammals :  thus  we  have  the 
lip-finger  of  the  rhinoceroses  and  the  prominent 
lip  and  nose  of  the  tapirs  and  of  the  saiga-antelope. 
Moreover,  our  excellent  anatomist  Burmeister 
(whether  rightly  or  wrongly  I  do  not  venture  to 
say)  has  equipped  the  Macrauchenia,  probably  one 
of  the  horse  family  from  the  Pliocene  deposits  of 
Patagonia,  with  an  appendage  resembling  an  ele- 
phant's trunk  (Fig.  39). 

Be  that  as  it  may,  at  all  events  our  present  Ele- 
phant is  one  of  the  strangest  and  most  enigmatical 
forms,  which,  moreover,  must  have  impressed 
uncivilised  nations  in  an  extraordinary  manner. 


THE  PROBOSCIS,  OK  ELEPHANTS. 


229 


We  do  not  put  much  faith  in  the  Indian  legend, 
according  to  which  the  monsters  which  the 
Great  Spirit  destroyed  by  lightnings,  and  which 
died  without  leaving  offspring,  were  Mastodons 
(which  existed  in  America  as  the  earliest  contem- 


Fio.  39. — ATacrauchenia  patagonia.    After  Burmelster. 

poraries  of  man),  still,  A.  W.  Schlegel  as  early  as 
1883 l  pointed  out  in  one  of  his  classic  inquiries 
that  the  influence  exercised  by  the  elephants  upon 
the  imagination  of  the  Hindoos  was  positively  all- 

1  A.  W.  Schlegel,  Indische  Bibliothek,  1823. 


230  THE  MAMMALIA 

powerful.  The  Hindoos  marvelled  at  everything  in 
the  animal,  not  only  at  its  sagacity,  which  made  it 
seem  to  them  the  embodiment  of  the  god  Ganesa, 
but  also — and  more  justly  than  we — they  admired 
the  neatness  of  its  feet. 

Its  zoological  singularity  is,  as  already  stated, 
mainly  centred  in  the  character  of  its  head.  To- 
gether with  an  unusually  small  breadth  of  head, 
the  facial  portion  shows  a  remarkable  height.  The 
narrowness  is  caused  by  the  very  limited  number 
of  teeth.  In  the  upper  jaw  there  are  only  the  two 
tusks  (incisors)  and  one  molar  on  either  side ;  in 
the  lower  jaw  there  are  molars  only,  powerfully 
developed,  it  is  true,  but,  as  regards  length,  show 
comparatively  far  less  dimension  than  is  seen  in 
the  full  dentition  of  a  grass-eater.  All  the  more 
powerful  and  higher  are  the  roots,  not  only  of  the 
tusks  but  of  the  molars.  The  latter  are  changed 
six  times,  so  that  the  succeeding  teeth  from  be- 
hind and  below  claim  a  position  in  the  inside  of 
the  jaw  till  the  animal  is  tolerably  advanced  in 
years.  The  structure  of  the  molar,  even  when 
worn  smooth  by  use,  shows  it  to  be  an  exceedingly 
perfect  apparatus  for  crushing  leaves  and  grasses. 
Zoology  terms  it  *  complex.'  It  appears  to  be 
formed  of  a  large  number  of  high  and  narrow 


THE  PKOBOSCIM), ,  OR  ELEPHANTS.  231 

cases  of  enamel  which  are  filled  with  dentine  and 
joined  into  one  mass  by  cement.  This  account  of 
the  formation  of  the  tooth,  which  is  universally 
accepted  by  descriptive  zoology,  is,  however,  as  we 
shall  see,  not  correct,  and  very  unnecessarily  makes 
the  gap — which  does  exist  between  the  Elephants 
and  the  other  plant-eaters — appear  greater  than 
need  be. 

Even  Cuvier  distinguished  among  the  Elephants 
a  group  of  fossil  trunk-bearers,  perfectly  of  the 
elephant  type,  but  with  a  more  complete  dentition ; 
the  molars,  although  less  large  than  those  of  the 
elephants,  being  characterised  by  nipple- shaped 
eminences  or  tubercles  in  pairs,  forming  a  number 
of  transverse  ridges.  Cuvier  called  the  genus 
Mastodon.1  A  mastodon  tooth  of  this  kind  (Fig. 
40)  presents  nothing  specially  striking  apart  from 
its  often  remarkable  size.  The  crown,  however,  is 
distinguished  by  the  extraordinary  strength  of  the 
connecting  layer  of  enamel  which  does  not  pene- 
trate in  folds  into  the  interior.  Now,  as  three 
molars  of  this  kind  with  huge  tuberculated  crowns 

1  The  most  important  contributions  on  this  subject  are: 
Vacek,  «  Ueber  osterreichische  Mastodonten  und  ihre  Beziehungen 
zu  den  Mastodonten  Europa's,'  Abhatidlungen  der  geologischen 
Beichsanstalt,  vii. :  most  admirable  also  is  the  chapter  on  the 
f  Elephantoides  '  in  Gaudry's  Mammifores  lertiaires. 


232 


THE  MAMMALIA. 


are  met  with  in  a  row  at  the  same  time  (for 
instance,  in  the  widely  distributed  Mastodon  angus- 
tidens) ;  and  as,  moreover,  they  follow  upon  one 
another  as  milk  teeth  and  permanent  teeth ;  and, 
further,  as  several  typical  mastodons  of  this  kind 


Fio.  40. — The  used  Molar  of  Mastodon  angustidens. 
a  a',  b  b',  c  c',  Transverse  ridges ;  one-half  nat.  size. 

have,  besides  the  upper  tusks,  lower  ones  as  well, 
and  between  them  other  two  smaller  incisors, 
this  species  of  dentition  moves  wholly  within 
the  limits  and  forms  known  to  us.  The  mastodons 
referred  to  are  those  of  the  Middle  and  Upper 


THE  PKOBOSCIDJE,  OE  ELEPHANTS.          233 

Miocene,  which  survived  longer  in  America  than  in 
the  Old  World,  and  one  of  which  continued  to  exist 
up  to  the  period  of  the  Diluvial  deposits  and  turf 
formations,  most  probably  even  up  to  the  prehis- 
toric times  of  the  human  race.  This  is  the  so- 
called  Ohio  animal,  the  Mastodon  giganteum. 


b' 


FIG.  41.  -  Portion  of  a  Molar  of  Mastodon  elephantoid.es. 
One-half  nat.  size.    After  Clift. 

As  early  as  the  Upper  Miocene  we  meet  with 
animals  of  the  Mastodon  species,  with  molars,  the 
ridges  of  which  are  much  more  sharply  denned  and 
resemble  rows  of  miniature  roofs  (Fig.  41),  inas- 
much as  they  consist  of  numerous  small  tubercles, 
which  almost  coalesce  with  one  another.  The  tops 


234  THE  MAMMALIA. 

of  these  tubercles  become  more  or  less  rubbed  off 
with  age.  Only  in  some  cases  are  the  furrows 
between  the  ridges  of  the  tooth  somewhat  filled  with 
cement.  These  differing  varieties  and  intermediate 
forms  have  obviously  proceeded  from  the  earlier 
mastodons,  and  in  order  to  simplify  the  arrange- 
ment have  been  classed  as  the  genus  Stegodon. 
Their  home  was  chiefly  in  Italy,  whence  they 
spread  abroad  as  far  as  Japan.1  The  discovery  of 
their  remains  in  the  Japanese  Archipelago  is  a 
proof  that  these  islands  did  not  lose  their  connection 
with  the  continent  till  comparatively  recent  times. 
These  teeth  prepare  us  for  the  molar  of  the 
true  elephant,  the  latest  form  of  the  group.  It 
originates — and  indeed  not  in  theory  but  in  the 
actual  transition  forms  up  to  the  living  species — 
by  the  ridges  continuing  to  become  steeper,  drawing 
closer  to  one  another,  and  sinking  down  almost  to 
the  root  of  the  tooth,  and  by  these  furrows  be- 
coming filled  with  cement,  which  thence  covers  the 
whole  outward  surfaces  of  the  tooth.  The  enamel 
parts  of  the  still  unused  tooth — although  in  form 
and  extent  extraordinarily  changed— nevertheless 
show  the  same  connection  as  in  the  species  from 

1  Naumann,     Ueber    japanische    Elephanten    der    Vorzeit 
Palceontographica,  vi.  1882. 


THE  PROBOSCIS,   OE  ELEPHANTS.  235 

which  we  started.  A  comparison  of  Figs.  40,  41, 
42  will  make  the  homology  of  the  spaces  a  a't  b  b't 
c  c'  perfectly  clear. 

Europe,  before  the  appearance  of  the  Glacia 


Fia.  42.— Piece  of  a  Molar  of  the  Mammoth,  cut  longitudinally, 

Nat.  size. 
e,  Enamel ;  d,  dentine ;  c,  cement. 

period,  possessed  several  elephants,  and  Britain, 
which  at  that  time  had  not  yet  been  rent  asunder 
from  the  continent,  possessed  the  Elephas  antiquus, 
and  Italy  the  Elephas  meridionaUs.  The  Mammoth 


236  THE  MAMMALIA. 

also — the  Eleplias  primigenius,  the  most  frequently 
mentioned  and  most  widely  distributed  animal  of 
the  group — had  been  driven  from  Asia  into  Central 
Europe,  whether  as  far  as  England  is  still  uncer- 
tain. It  had  an  associate  in  the  Elephas  antiquus ; 
but  in  any  case  the  mammoth  survived  it  up  to  the 
period  of  man.  Yet  it  can  scarcely  be  said  whether 
— at  the  time  the  human  immigrant  took  possession 
of  Europe,  and  the  struggle  began  between  the 
tamed  and  the  wild  races,  between  man  and  the 
wolf  in  England,  and  the  lion  in  Thessaly — the 
mammoth  was  exterminated  in  this  kind  of 
struggle,  or  whether  it  succumbed  to  climatic,  i.e. 
to  natural  influences  unknown  to  us.1 

In  entering  upon  a  discussion  of  the  elephants 
as  a  class,  it  was  our  wish  to  do  away  with  what 
mystery  seemed  to  encompass  the  existence  of  the 
present  animal,  and  we  have  done  so  by  pointing 
out  their  undoubted  descent  from  the  Miocene 
mastodons.  There  is  but  one  other  step  backwards 
that  we  can  take  in  explanation  of  the  connection, 
by  bringing  forward  another  of  the  colossal,  thick- 
skinned  animals,  the  Dinotherium.  Up  to  within 
very  recent  times  only  its  skull  was  known  (Fig. 

1  Dawkins,  '  The  British  Pleistocene  Mammalia,'  Palceonto- 
(jraphical  Society,  1878,  xxxii. ;  Adams,  '  Monograph  on  the 
British  Fossil  Elephants,'  Ibid.  1877. 


THE  PKOBOSCID^E,  OR  ELEPHANTS.          237 

43),  from  which  it  was  supposed  to  be  a  footless, 
aquatic  animal,  and  that,  by  means  of  its  two 
tusks  which  projected  from  the  lower  jaws  and 
curved  downwards,  it  probably  moored  itself  to  the 
shore  while  resting  or  sleeping.  No  whole  skeleton 
of  this  animal  has,  it  is  true,  yet  been  discovered 
in  connection  with 
the  skull,  but  to 
judge  from  various 
remains  of  bones, 
which  in  all  pro- 
bability belonged  to 
it,  it  seems  certain 
that  the  structure 
of  the  Dinotherium 
was  of  the  Elephant 
species,  and  that 

some  kind   of  pro-   FIG.  43. — Skull  of  Dinotherium  gigan- 

boscis  must  be  sup-  teum'  One  twenty-fourth  nat- size- 
posed  to  have  been  suspended  from  the  elongated 
nasal  bones.  It  is  restored  thus  in  our  most  eminent 
works  on  palaeontology,  and  the  correctness  of  the 
supposition  is  confirmed  by  a  comparison  of  the 
molars  with  those  of  the  early  mastodons.  The 
form  and  manner  of  succession  of  these  molars,  five 
being  able  to  be  in  use  at  the  same  time,  lead  to 


238  THE  MAMMALIA. 

the  conclusion  that  the  molars  of  the  older  masto- 
dons originated  from  those  of  the  Dinotherium  by 
the  loss  of  one  or  more  of  the  front  milk-teeth  as  the 
result  of  the  strengthening  of  the  true  molars.  But 
as  the  known  Dinotheridse  and  the  earlier  masto- 
dons occur  in  almost  the  same  geological  horizons, 
the  supposed  descent  cannot,  of  course,  signify  that 
Dinotherium  giganteum  had  changed  into  the  Mas- 
todon  angustidens,  but  only  indicates  the  way — 
where  and  how — the  mastodons  have  originated 
from  ancestors  of  the  Dinotherium  species. 

As  is  evident  from  Weinsheimer's  classification ! 
— our  latest  authority  for  the  species — remains  of 
the  Dinotherium,  and  more  especially  molars  and 
lower  jawbones,  are  found  in  various  parts  of  the 
Old  World ;  but  in  all  cases,  only  in  the  Tertiary 
deposits,  and  in  no  case  higher  than  in  the  Upper 
Miocene  strata ;  it  ranged  from  France  as  far  as 
India.  In  England  no  traces  of  it  have  been 
found,  and  its  southern  limit  in  Europe  is  Greece 
(Pikermi).  Notwithstanding  the  different  forms 
and  sizes  of  the  teeth — according  to  which  fifteen 
species  have  been  distinguished — still,  owing  to 
the  transitions  met  with  everywhere,  we  are  in- 

1  Weinsheimer,   Ueber  Dinotherium  giganteum,  K,    Berlin, 
1883. 


THE  PKOBOSCID^E,  OR  ELEPHANTS.          239 

clined,  with  Weinsheimer,  to  assume  only  one 
species,  the  Dinotherium ;  we  are  also  glad  to  be 
reminded  by  him  of  Suess'  words  :  '  We  can  readily 
convince  ourselves  that  physical  changes  occur 
without  the  mammal  of  the  district  being  much 
affected  by  them,  but  we  find  no  change  in  the 
animal  world  without  a  change  in  the  outward 
circumstances,  without  some  recognisable  episode.' 
The  changes  in  the  dentition  of  the  Dinotheriaa 
(which  appear  somewhat  earlier  than  the  masto- 
dons) to  the  elephants  proper,  correspond  with  the 
gradual  change  in  their  food  and  mode  of  life. 
The  Dinotheriae  and  the  older  mastodons  had  to 
subsist  mainly  upon  the  roots  and  stalks  of  water- 
plants,  which  they  tore  up  with  their  lower  tusks 
in  the  morasses  of  tropical  climes,  like  the  rhinoce- 
roses. Harder  grasses  demanded  and  produced 
the  transformation  of  the  simple  ridged  tooth, 
the  tuberculate  teeth  of  the  mastodons,  the  fall- 
ing away  of  the  front  milk-teeth,  and  finally  a 
concentration  of  the  material  force,  and  more 
especially  the  peculiar  conformation  of  the  molar 
of  the  later  and  present  elephants.1  They  certainly 

1  '  All  the  changes  of  the  organisation  which  we  may  observe 
in  the  later  forms  of  Mastodon  as  compared  with  the  earlier 
ones — for  instance,  the  different  forms  of  the  incisors,  the  re- 
duction of  the  symphysis  (i.e.  the  connecting  parts  of  the  lower 


240  THE  MAMMALIA. 

have  differentiated  much  more  from  the  original 
form  than  the  other  plant-eaters ;  but  even  in  the 
case  of  these  latter,  a  similar  course  from  the 
general  disposition  to  the  specialised  form  of  to-day 
has  been  pointed  out.  Thus,  at  the  close  of  this 
short  chapter,  our  elephants  cannot  any  longer  be 
said  to  stand  as  inexplicable  wonders  of  creation. 

In  the  Middle  Eocene  deposits  westwards  of  the 
Eocky  Mountains,  there  have  been  discovered,  among 
many  other  animal  forms,  numerous  remains  of 
powerful  plant-eaters  of  the  size  of  elephants  ;  their 
skull  possessed  two  or  three  pairs  of  horns,  and 
the  upper  jaw  showed  gigantic  canines  (Fig.  44). 
These  Dinocerata  are  believed  by  Marsh  and  Cope 
(and  with  some  degree  of  probability)  to  be  de- 
scendants of  the  Coryphodonta  (see  above,  p.  199), 
and  although  the  possibility  of  their  being  related 
to  trunked -animals  is  not  excluded,  still  meanwhile 
it  is  a  mere  vague  analogy.  The  Brontotheriae 
from  the  Lower  Miocene  eastwards  of  the  Eocky 
Mountains,  which  are  likewise  colossal  creatures, 

half  of  the  jaw),  the  increased  slowness  in  the  succession  of  the 
teeth,  and  the  corresponding  increase  in  the  number  of  ridges, 
in  short,  the  dentine  which  by  degrees  becomes  worn  off — point  to 
the  fact  that  the  later  mastodons  had  discontinued  the  mode  of 
life  practised  by  their  ancestors,  and  had  adapted  themselves  to 
a  life  on  land.' 


THE  PEOBOSCID^E,  OR  ELEPHANTS.  241 

but  less  striking  as  regards  the  formation  of  their 
skull,  may,  with  somewhat  greater  certainty,  be 
classed  as  a  branch  of  the  Khinoceros  tribe  (see 
above,  p.  199).  Both  groups,  however,  strike  us 
nevertheless  as  somewhat  strange,  chiefly  because 
their  brain  can  be  compared  only  with  that  of 
certain  fossil  reptiles,  considering  the  size  of  the 


FIG.  44. — Skull  of  Dinoceras  mirabile.     One-nineteenth. 
After  Marsh. 

skull  and  the  thickness  and  mass  of  the  spinal 
marrow.  It  would  seem  to  be  a  lower  form  even 
than  that  of  the  Marsupials  and  the  Monotrema. 

Two  other  small  groups  are  allied  to  the  Hoofed 
Animals,  but  in  regard  to  one  of  these,  the  genus 
Hyrax  (rock  conies),  no  more  can  be  said  to-day 


242  THE  MAMMALIA. 

than  what  was  known  to  Cuvier.  Although  the  two 
groups,  in  their  outward  appearance  and  mode  of 
life,  show  affinity  to  the  Eodents  with  claw-like 
hoofs,  their  molar  teeth  are  singularly  like  those  of 
most  of  the  Ehinoceros  tribe.  There  is  absolutely 
no  safe  starting  point  for  their  historical  descent.1 
We  are  more  fortunate  as  regards  the  class  next 
to  be  considered,  the  Sirenia. 

6.    THE    SIRENIA,    OB    SEA-COWS.2 

Of  this  group  the  dugong  (Halicore  dugong) 
lives  in  the  Ked  Sea,  the  Manatus  frequents  the 
West  Coast  of  Africa,  and  another  species  the 

1  Cope  is   inclined  to  think  that  the   arrangement  of  the 
carpals  in  the  Hyrax  is  a  sign  of  very  ancient  descent.    His 
main  reason  for  this  supposition  is  the  fact  that  the  bones  form- 
ing the  several  rays  of  the  fingers  still  lie  one  behind  the  other 
simply  and  regularly,  as  in  the  case  of  the  lower  vertebrates ; 
whereas  in  other  mammals — not,  however,  in  the  elephant — the 
two  rows  of  carpals  have  been  displaced  and  lie  side  by  side. 
The  cause  of  this  displacing  or  twisting  must,  without  doubt,  be 
looked  for  in  the  loss  of  the  thumb,  which  again  is  connected 
with  the  cases  of  adaptive  and  inadaptive  transformations  of  the 
carpals  mentioned  by  Kowalewsky.    As,  however,  in  the  elephants 
the  row  of  carpals  is  not  displaced,  while  in  the  Coryphodons  a 
very  marked  displacement  has  taken  place  in  spite  of  the  thumb 
having  been  retained,  it  seems  to  me  that  Cope's   attempt  to 
arrange  and  determine  the  general  relationships  of  the  Hoofed 
Animals,  more  particularly  of  the  earliest  Eocene  fauna,  from 
these  circumstances,  is  much  too  unsafe. 

2  Lepsius,  Halitheriuvn  Schinzii.    Darmstadt,  1881. 


THE  SIRENIA,  OK  SEA-COWS.  243 

eastern  shores  of  America.  Another  and  fourth 
species  of  very  remarkable  form,  the  Ehytina 
stelleri,  belonged  to  our  present  period,  but  owing 
to  the  smallness  of  the  range  of  its  distribution, 
seems  to  have  become  extinct  between  the  years 
1741-48. 

The  earlier  systems  of  zoology  considered  the 
want  of  hind  legs  in  Whales  and  the  Sirenia,  the 
paddle- shaped  form  of  their  front  limbs,  and  the 
formation  of  the  end  of  the  body  into  an  horizon- 
tally extended  fin,  to  constitute  the  characteristic 
features  of  a  distinct  order  of  animals,  compared 
with  which  other  very  marked  differences  in  their 
skull  and  dentition  seemed  of  little  importance. 
However,  nowadays  we  are  so  well  acquainted 
with  the  disappearance  of  the  front  or  back 
limbs,  or  of  both  extremities  (in  the  case  of 
reptiles)  as  phenomena  of  convergence,  without 
this  being  considered  a  proof  of  any  near  blood- 
relationship,  that  we  no  longer  think  of  classing 
the  Sirenia  with  the  Whales  simply  because  of  the 
want  of  the  hind  limbs.  The  Whales  are  flesh- 
eaters,  the  Sirenia  plant- eaters  ;  the  former,  by 
their  relationship  to  the  seals,  belong  to  the  order 
of  the  Fera,  flesh-eaters  in  the  narrower  sense  of 


244  THE  MAMMALIA. 

the  word  ;  the  latter  are  a  very  ancient  branch  of 
the  Hoofed  Animals. 

Of  the  living  Sirenia  the  Manatus  shows  the 
fullest  dentition  with  a  change  of  teeth.  It  points 
to  an  old  Tertiary  group  found  in  Jamaica,  the 
Prorastomus  sirenoides,  whose  molars  are  genuine 
ridged  teeth. 

The  other  and  more  perfect  line  ends  in  the 
present  period  with  the  so-called  Steller's  Sea-Cow 
(Bhytina  stelleri),  which  has  recently  become  ex- 
tinct. It  had  no  true  teeth  for  masticating  pur- 
poses, but,  in  place  of  molars,  had  large  fibrous 
structures  on  the  gums,  one  on  each  side  of  each 
jaw.  These  structures  occur  also  in  two  of  the 
living  species,  but  are  less  large.  The  dugong 
already  shows  a  considerable  loss  of  teeth,  but  by 
possessing  them  stands  nearer  to  the  earlier  form 
of  Sirenia,  which  leads  in  a  direct  line  back  to  the 
Eocene  Halitherium.  The  dental  formula  is  : 

.1         1?      3         4 


When  comparing  the  genuine  Hoofed  Animals 
with  their  ancestors,  it  was  seen  that  the  loss  of 
one  or  two  toes  took  place  as  early  as  in  the  first 
Tertiary  division.  It  was  only  single  genera,  such 


THE  SIRENIA,  OR  SEA-COWS.  245 

as  Coryphodon,  that  still  showed  the  old  five-toed 
extremity,  an  inheritance  from  Pre- Tertiary  times. 
However  all  the  living  Sirenians  possess  a  five- 
fingered  hand.  When,  therefore,  it  is  said  that  the 
molars  of  Prorastomus  are  genuine  ridged  teeth, 
these  do  not  point  to  the  true  Lophiodonta  and 
tapirs,  with  their  already  reduced  hand,  but  to 
earlier  ancestors  on  both  sides.  Thus  things  no 
longer  existing  point  to  that  very  distant  past, 
which  extends  back  beyond  our  actual  observa- 
tions. Even  in  the  case  of  Halitherium  all  that 
is  left  of  the  hind  limb  is  the  thigh-bone.  This 
bone,  however,  is  still  attached  to  the  pelvis, 
which  is  tolerably  reduced,  but  has  a  socket.  The 
earliest  Sirenians,  therefore,  had  a  less  striking 
form  of  skull,  but,  nevertheless,  in  their  whole 
appearance  were  already  like  the  present  living 
species.  From  this  it  follows  that  the  four-* 
footed  mammals  changed  their  abode  for  the  sea, 
and  lost  their  hind  limbs,  before  the  Tertiary 
period. 

The  living  Sirenians  have  experienced  a  still 
farther  reduction  of  the  pelvis ;  it  has  become  de- 
tached from  the  vertebral  column ;  and  even  the 
above-mentioned  remnant  of  the  hind  limb,  the 
rudimentary  thigh-bone,  has  wholly  disappeared. 


246  THE  MAMMALIA. 


7.    THE    CETACEA,    OR   WHALES. 

Up  to  about  the  year  1840,  our  scientific 
knowledge  of  the  larger  Whales  was  based  almost 
exclusively  upon  the  dissection  of  a  few  stranded 
animals  made  in  most  cases  in  a  very  superficial 
manner.  Skeletons  of  the  animals  could,  of  course, 
be  procured,  and  some  complete  specimens  had  been 
set  up  in  some  of  the  museums.  Their  ribs,  lower 
jaws,  and  vertebrae  had  also  been  collected,  and, 
like  the  bones  belonging  to  fossil  elephants,  were 
chained  to  town-halls  and  churches,  where  they 
were  gazed  at  as  the  remains  of  giants,  and  pro- 
bably also  (as  was  the  case  with  a  mammoth's 
thigh  bone  in  Spain)  were  worshipped  as  the 
reliques  of  saints  of  giant  stature. 

Owing  to  this  manner  of  acquiring  scientific 
material,  a  fatal  confusion  had  arisen  in  the  names 
given.  It  was  about  this  time  that  Eschricht, 
professor  of  physiology  in  Copenhagen,  applied  the 
well-known  lines — '  If  thou  the  poet  would'st  under- 
stand, Then  must  thou  go  to  the  poet's  land,' — 
to  the  Cetaceans.  He  did  not  visit  them  himself, 
it  is  true,  but  his  friend  Holboll,  who  was  for  many 
years  inspector  of  the  Danish  colonies  in  Green- 
land, undertook,  at  Eschricht 's  request,  to  make 


THE  CETACEA,  OE  WHALES.  247 

collections  and  observations  on  the  shores  of  the 
Arctic  Ocean.  Holboll  furnished  the  museum  of 
Copenhagen  with  excellent  material  in  the  way  of 
skeletons,  together  with  the  softer  portions  of  the 
body,  also  whole  animals  of  various  ages,  with 
detailed  accounts  of  the  biological  observations  he 
had  made.  All  this  information  Eschricht1  made 
use  of  in  a  classic  work,  where  he  traces  the  trans- 
formation of  the  skull  of  the  foetus  (only  some  few 
feet  in  length  altogether)  to  that  of  the  full-grown 
giant,  that  framework  which  strikes  the  on-looker 
at  first  as  perplexingly  strange.  He  cleared  up  the 
relation  between  the  bearded  and  the  toothed  Whales 
by  following  up  Geoffrey's  discovery  more  minutely, 
i.e.  by  showing  that  the  foetus  of  the  Bearded  or 
Whalebone  whale  possesses  a  number  of  small  teeth, 
which  never  cut  through  the  gums,  and  subsequently 
become  completely  re-absorbed,  when  the  huge 
sieve-like  apparatus  on  the  mucous  membrane  of 
the  gum  appears.  The  rudimentary  teeth  of  the 
Whalebone  whales,  which  never  come  into  use,  are 


1  Eschricht,  Zoologisch-anatomisch-physiologische  Untersuch- 
ungen  Uber  die  nordischen  Walthiere  (Leipzig,  1849),  of  which 
work  there  is  an  English  translation  ;  also  Brandt,  *  Untersuch- 
ungen  iiber  die  fossilen  und  sub-fossilen  Cetaceen  Europas,' 
M&m.  Acad.  Petcrsb.,  1873  ;  Van  Beneden  et  Gervais,  Ostdographie 
des  Cttacis.  Paris,  1868-80. 


248  THE  MAMMALIA. 

final  links  in  the  chain  of  evidence  that  the  Whale- 
bone whales  are  the  last  members  of  a  transformed 
group  which  commenced  with  animals  with  four 
toes  and  numerous  teeth,  and  which  by  the  gradual 
diminution  of  the  dentition  have  become  Whale- 
bone whales. 

Still,  the  skull  of  the  Whalebone  whales  shows  so 
much  resemblance  to  that  of  the  Dolphins  and  all 
of  the  other  toothed  whales,  that,  were  it  not  for 
the  discovery  of  teeth  in  the  foetal  animal,  we  should 
be  in  doubt  as  to  the  unity  of  the  two  groups. 
From  the  head  of  a  dolphin  only  a  few  feet  in 
length,  we  may  learn  all  about  the  peculiar  trans- 
formations just  as  well  as  from  the  head  of  a 
Greenland  whale.  The  mid  jawbones  (Fig.  45) 
do  not  appear  in  front  between  the  upper  jaw- 
bones, but  are  very  much  elongated,  and  fre- 
quently lie  somewhat  irregularly,  projecting  beyond 
the  upper  jawbone.  The  most  striking  changes, 
however,  are  those  of  the  middle  head,  and  all  this 
can  be  traced  to  the  rising  up  of  the  nasal  cavities 
— in  all  other  mammals  these  lie  horizontally  or 
obliquely  towards  the  front — which  form  perpen- 
dicular blow-holes  close  to  the  crown  of  the  head. 
Not  only  has  the  olfactory  bone  become  raised, 
but  the  nasal  bones  also,  in  most  cases,  have 
been  completely  displaced  from  their  position  as 


THE  CETACEA,  OK  WHALES. 


249 


coverings,  and  stand  as  perpendicular  back  walls  to 
the  nose,  while  the  frontal  and  parietal  bones  are 
compressed  and  pushed  aside  in  the  most  remark- 
able manner.  However,  it  would  certainly  not  re- 
quire a  practised  osteologist  to  construct  the  skull 
of  a  whale  from  any  certified  bone.  There  is 
nothing  in  the  skull  of  the  whale  that  could,  in  the 


FIG.  45.-  Skull  of  Delphinus  lagenorhynchus.    Gray. 

*  k,  Mid-jawbones ;  o  k,  upper  jawbone  ;  j,  cheek-bone  ;  p,  parietal ;  *,  frontal 
bone ;  »,  nasal  bone  ;  e,  olfactory  bone.    One-fifth  nat.  size. 

slightest  degree,  lead  to  a  connection  between  it 
and  the  Sirenians  (p.  243).  Nevertheless,  their  hind 
limbs,  like  those  of  the  Sirenians,  have  disappeared 
externally  without  leaving  a  trace  of  their  former 
existence;  the  rudimentary  pelvic  bones  that  are 
concealed  in  the  flesh — sometimes  with  the  last  rem- 
nant of  the  thigh-bone,  very  rarely  with  the  shank 
23 


250 


THE  MAMMALIA. 


— bear  witness,  however,  to 
their  having  possessed  an- 
cestors with  four  legs.1 
The  front  limbs  remain 
wholly  within  the  known 
structure  of  the  mammal 
leg,  as  may  be  seen  by 
that  of  the  dolphin  on  Fig. 
46.  The  toothed  whales 
are  almost  without  excep- 
tion five-fingered,  even 
though  in  most  cases  the 
thumb  and  the  little  finger 
appear  very  much  reduced. 
This,  moreover,  shows  them 
to  be  geologically  older  than 
the  Whalebone  whales ;  for 
of  these  only  the  smooth 
whales  (Bal&na)  possess  five 
fingers ;  in  the  others  the 
thumb  has  completely  dis- 

1  The  modifications  which  the 
whales  have  experienced  as  mam- 
mals in  water,  have  been  admir- 
FIO.  46.— Eight  Fore-limb  of    ably  described    by  Prof.   Flower, 
Delphinus  delphis.    After    '  Whales  in  the  Past  and  Present,' 
van  Beneden  and  Gervais.    Kosmos,  vii.  1883. 


ff 


THE  CETACEA,  OR  WHALES.  251 

appeared.  That  the  Whalebone  whales  are  geologi- 
cally younger  than  the  smooth  whales  is  likewise 
proved  by  their  generic  characters,  the  furrow  which 
extends  from  the  throat  to  the  belly,  and  the 
humped  or  fin-shaped  protuberance  on  the  back. 
Hence  not  only  does  the  preserved  skull  of  one  of  the 
most  important  group  of  the  "Whalebone  whales 
(the  Cetotherium)  oblige  us  to  maintain  the  animal 
to  have  been  one  of  the  smooth  whales,  but  we  are 
also  enabled,  from  this  circumstance  and  the  geo- 
logical period,  to  conclude  that  these  whales  did  not 
possess  either  furrows  on  their  breast  or  fins  on 
their  back. 

The  time  of  the  fullest  development  of  the 
Cetacea  belongs  to  the  Miocene  period,  when  they 
had  associates  in  the  large  and  also  numerous  small 
Whalebone  whales,  for  instance,  the  Cetotherium 
just  mentioned,  which  is  closely  related  to  the 
present  Bearded  or  Whalebone  whales  (from  two  to 
ten  feet  long),  and  also  the  Dolphins  and  the  Zeu- 
glodonta.  The  last-mentioned  group  is  formed  of 
the  two  entirely  extinct  genera,  Zeuglodon  and 
Squalodon. 

Brandt  has  in  detail  urged  it  as  improbable 
that  Zeuglodon,  as  is  often  supposed,  can  be 
regarded  as  an  intermediate  form  between  the 


252  THE  MAMMALIA. 

seals  and  whales,  the  shape  of  the  skull  and 
the  strong  nasal  bones  covering  the  nasal  cavity 
having  been  thought  to  indicate  this.  Their  length 
varies  between  twelve  to  seventy  feet.  They  belong 
in  America  to  the  Eocene,  in  Europe  to  the  Mio- 
cene period. 

Squalodon  approaches  closer  to  the  Dolphins 
than  does  Zeuglodon,  more  particularly  by  the 
position  of  the  nasal  bones  and  the  corresponding 
displacement  of  the  other  bones.  Its  teeth  (Fig. 
47),  like  those  of  the  Zeuglodonta,  remind  one  of 

31          4 

the  Seals.     The  dental  formula  is  :  i  -,  c  -,  pm    , 

31          4 

17 

ra  -.     The  compressed  molars,   which   are  pyra- 

midical  in  form,  show  a  certain  external  resemblance 
to  the  teeth  of  the  Sharks. 

As  the  Zeuglodonta — including  the  Squalodonta 
— are  not  yet  as  far  advanced  in  the  transformation 
of  their  skull  as  the  Delphinidae,  it  has  never  oc- 
curred to  anyone  to  regard  the  Dolphins  as  ances- 
tors of  the  Zeuglodonta.  Such  a  supposition  would 
be  as  irrational  as  if  we  were  to  imagine  the 
Antelopes  descended  from  Oxen.  On  the  other 
hand,  however,  as  great  a  difficulty  would  have  to 
be  faced  were  we  to  suppose  that  animals  of  the 
Squalodon  species  had  left  descendants  of  the 


THE  CETACEA,  OK  WHALES. 


253 


Dolphin  species.  We  do  not  speak  of  the  dolphin- 
like  whales  with  reduced  dentition — e.g.  the  Nar- 
whales ;  these  are  side  branches  of  the  main  stem, 
the  members  of  which  are  distinguished  by  numer- 
ous teeth  of  the  same  shape.  The  teeth  are  always 
growing  and  have  no  closed  roots,  wherein  they 
resemble  those  of  many  of  the  reptiles.  Now 
Baume,  for  various 
good  reasons,  has 
made  it  seem  probable 
that  the  ever-growing 
teeth  of  mammals  are 
an  ancient  inherit- 
ance, and  that  rooted 
teeth,  on  the  other 
hand,  are  a  new  ac- 
quisition. If  Baume 
is  right  in  this,  we 
have  no  connecting 
link  for  the  Dolphins, 
and  naturally  none  either  for  the  Whalebone  whales. 
All  the  three  subdivisions — Zeuglodonta,  Dolphins, 
and  Whalebone  whales — are  found  side  by  side  in 
the  Early  Tertiary  period,  and  the  vertebrae  of 
whales  have  even  been  found  in  the  Jura.  How- 
ever, all  that  can  be  said  with  certainty  is  that  we 


FIG.  47.— Tooth  of  Squalodon. 

a,  From  the  outside ;  &,  from  the  side. 
After  Sites. 


2.54  THE  MAMMALIA. 

have  no  idea  in  what  period  or  under  what  circum- 
stances whales  came  to  be  developed.  "What  is 
improbable  is  that  they  were  descended  directly 
from  reptile-like  ancestors,  independently  of  the 
other  mammals.  None  of  their  peculiarities  point 
directly  to  the  Keptiles,  and  are  all  intelligible  as 
modifications  which  were  effected  by  the  land 
animal  in  its  transition  to  a  life  in  water. 

But  of  what  kind  were  these  ancestors  ?  Our 
first  thought  turns  to  the  Seals,  which,  of  course, 
have  likewise  adapted  themselves  to  an  aquatic 
life.  However,  in  their  case,  the  hind  limbs  have 
not  in  any  way  become  reduced,  and  have  only 
changed  their  position  to  the  pelvis ;  whereas  the 
upper  and  lower  parts  of  the  leg  are  shortened,  and 
the  feet  have  become  broad  and  lengthened  paddles. 
Hence  it  cannot  be  imagined  that  these  animals, 
which  are  so  admirably  equipped  for  swimming, 
could  have  struck  out  a  new  kind  of  adaptation. 
There  could  not  have  been  any  use  or  necessity 
for  this.  Hence  a  certain  resemblance  in  the 
teeth  can  only  have  been  the  result  of  convergence ; 
and  Prof.  Flowers  reminds  us  that  this  had  long 
since  been  pointed  out  by  Hunter,1  who  says : 

1  John  Hunter,  '  Observations  on  the  Structure  and  Economy 
of  Whales,'  Philoso.  Trans.  1787. 


THE  CETACEA,  OR  WHALES.  255 

'  There  are  numerous  points  in  the  structure  of 
whales  which  bring  them  much  closer  to  the  hoofed 
animals  than  to  the  beasts  of  prey — for  instance, 
the  complex  stomach,  the  simple  liver,  the  respi- 
ratory organs,  but  mainly  the  reproductive  organs, 
and  the  stages  relating  to  the  development  of  the 
foetus.  Even  the  skull  of  Zeuglodon,  which  we 
admitted  shows  a  certain  likeness  to  that  of  the 
sea  dog,  shows  as  much  agreement  with  that  of  the 
earliest  pig- shaped  ungulates,  except  in  the  purely 
adaptive  character  of  the  form  of  the  teeth.'  The 
objection  raised  that  whales  are  flesh-eaters,  while 
most  of  the  Hoofed  Animals  are  true  plant-eaters, 
has  been  very  properly  refuted  by  Prof.  Flowers, 
who  points  to  the  former  predominance  of  omni- 
vorous animals,  and  shows  that,  with  the  exception 
of  the  Pigs,  which  have  remained  most  faithful  to 
the  ancient  type,  the  Omnivora  became  more  and 
more  true  grass-eaters,  while  the  others  developed 
a  taste  in  an  opposite  direction.  Eegular  flesh- 
eaters  can  either  not  accustom  themselves  to 
vegetable  food  at  all,  or  only  in  cases  of  emergency 
— as  we  ourselves  see  daily  with  the  cat  or  dog — 
whereas  we  not  unfrequently  find  instances  of 
the  contrary.  Cattle  eat  dried  fish  with  evident 
relish  during  a  northern  winter,  as  is  well-known ; 


256  THE  MAMMALIA. 

and,  therefore,  the  whales  may,  in  the  widest 
sense  of  the  word,  be  classed  with  the  primary 
Hoofed  Animals,  which  still  possessed  five  toes  and 
differed  as  much,  and  even  more,  from  the  present 
group  as  the  primeval  horses  from  the  horses  of 
our  day. 

The  period  when  whales  were  most  abundant 
was  that  of  the  Middle  Tertiary,  when,  as  already 
stated,  the  present  Europe-Asiatic  continent  was 
for  the  most  part  under  water.  Brandt  gives  a 
very  graphic  description  how  the  Cetacea  of  those 
temperate  zones  may  have  ceased  to  exist  with  the 
disappearance  of  that  ancient  ocean.  And  as  the 
account  is  of  general  importance  we  will  quote  his 
words  :  *  The  dying  out  of  marine  animals  appears 
at  first  sight  more  strange  than  the  dying  out  of 
land  animals.  We  are  apt  to  imagine  that  the  in- 
habitants of  the  sea — in  their  far-reaching  element 
animated  everywhere  more  or  less  by  living  creatures 
— have  a  better  opportunity  of  withdrawing  from 
such  external  influences  as  affected  them  injuriously, 
without  thereby  experiencing  a  want  of  food,  par- 
ticularly if  the  hurtful  changes  were  not  sudden. 
As  an  example  of  an  earlier  ocean  of  this  kind, 
extending  from  Western  and  Southern  Europe  to 
Central  Asia,  we  may  take  the  immense  ocean 


THE   CETACEA,   OB  WHALES.  257 

which  existed  in  the  Miocene,  and  probably  lasted 
beyond  that  period ;  when  largest  it  extended  to 
the  Arctic  ocean,  and  also  communicated  with  the 
tropical  seas  in  the  south.  An  ocean  of  this  kind 
would  not  only  confer  a  higher  temperature  upon 
the  central  zones,  but  would  also  essentially  con- 
tribute to  the  warmth  of  the  northern  regions, 
and  further,  would  not  merely  favourably  affect  the 
flora,  but  likewise  give  the  fauna  a  very  different 
character  to  what  it  shows  nowadays.  This  con- 
dition was,  however,  by  no  means  a  permanent 
one.  The  gradual  rising  of  the  land  led  to  a 
separation  of  the  southern,  sub-tropic  or  tropic 
seas,  and  to  a  lessening  of  the  extent  of  the  great 
ocean  itself,  and  its  temperature  would  likewise 
decrease.  This  was  still  more  the  case,  however, 
with  the  great  connecting  sea  in  the  north,  more 
particularly  when  its  separation,  and  gradual  dis- 
appearance, resulted  in  its  becoming  more  or 
less  detached  basins.  The  former  luxuriant  and 
fuller  vegetation  and  animal  life  on  the  continent, 
which  had  been  favoured  by  a  warmer  and  moister 
climate,  changed  their  character  and  became  less 
exuberant.  Less  organic  matter  being  produced 
on  the  land,  less  was  carried  to  the  ocean,  where 
it  served  numerous  small  marine  animals  as  food, 


258  THE  MAMMALIA. 

while,  at  the  same  time,  the  afflux  of  fresh  water 
exercised  a  greater  influence  upon  the  lessened 
amount  of  sea  water.  These  circumstances,  which 
reduced  the  food  of  marine  animals — nay,  which 
was  obviously  detrimental  to  their  existence  —were 
accompanied,  moreover,  by  the  gradual  separation 
of  the  great  ocean  into  numerous  basins,  occasioned 
by  the  rising  of  the  land  already  alluded  to ;  this 
prevented  the  animals  from  migrating,  and  the 
altered  condition  of  the  water  increased  even 
further  owing  to  the  separation.  As  a  proof  of 
this  we  have  the  Black  Sea,  the  Caspian,  and  the 
Aral  Sea,  which  remained  longest  in  connection, 
and  several  other  seas  in  Central  Asia.  Those 
species  of  invertebrates  and  fishes  which,  owing 
to  their  peculiar  organisation,  could  exist  only  in 
large,  open  seas,  and  not  in  an  inland  sea  with  a 
lesser  amount  of  salty  substances,  and  were  unable 
to  accommodate  themselves  to  the  change  in  the 
physical,  thermal,  and  biological  conditions,  died 
out  together  with  the  Cetacea.  Those  that  sur- 
vived and  were  able  to  adapt  themselves  to  circum- 
stances, like  some  of  the  molluscs,  &c.,  decreased 
in  size.' 


THE  CANID^E,  OB  DOGS.  259 

8.    THE    CARNIVORA,    OB   FLESH  EATERS. 

The  group  of  our  present  flesh-eating  mammals 
which  has  been  most  carefully  examined  as  regards 
specialisation  of  the  dentition,  and  whose  geological 
appearance  has  perhaps  left  most  traces  and  points 
of  connection — is  that  of  the  Dogs,  or  Canidce.  We 
shall,  therefore,  take  this  group  as  the  starting- 
point  for  our  comparative  examination. 

The  dog,  like  all  the  other  Carnivora,  possesses 
five  toes  on  its  front  feet  and  four  on  the  hind  feet, 
with  non-retractile  claws.  Those  who  wish  to 
obtain  even  a  limited  view  of  the  relationship 
between  the  main  genus  Canis  and  some  of  the 
sub-species,  and  various  other  forms  allied  to 
these,  their  geographical  distribution,  &c.,  in  the 
hope  of  finding  some  indications  of  the  lines 
which  partly  vanish  into  primeval  times  with- 
out leaving  any  trace,  but  again  in  many  in- 
stances showing  a  connection  with  definite  palae- 
ontological  facts,  must  first  of  all  make  them- 
selves acquainted  with  the  dentition  of  the  group. 
One  tooth  more  or  less  unmistakably  determines 
the  date  of  one  or  more  of  the  geological  periods. 
The  position,  size,  and  disappearance  of  the  teeth  in- 
dicate, with  almost  the  same  certainty,  the  relation- 


260  THE  MAMMALIA. 

ship  between  the  species  which  ranged  separated 
over  half  of  the  earth's  surface,  or  they  point  to 
the  different  origin  of  those  which  live  almost 
within  the  same  range  of  distribution.  The 
certainty  with  which  a  palaeontologist  works— by 
making  use  of  means  which  appear  absolutely 
valueless  to  an  unscientific  person — can  be  appre- 
ciated only  by  those  who  have  acquired  at  least 
some  knowledge  of  the  way  in  which  the  work  is 
accomplished.  This  again  shows  what  little  weight 
can  be  placed  in  the  perpetual  assertions  of  un- 
scientific persons,  that  the  followers  of  the  theory 
of  descent  are  not  in  the  position  to  prove  the 
transformation  of  species. 

Everyone  knows  that  the  dentition  of  the  fox 
(Canis  vulpes)  consists  of  very  differently  formed 
teeth  (Fig.  48),  which,  however,  agree  in  so  far 
that  the  crowns  show  an  unbroken  covering  of 
enamel ;  in  this  the  molars,  more  especially,  differ 
strikingly  from  those  of  the  Hoofed  Animals  and 
many  of  the  Eodents,  where  the  crowns  have  com- 
plicated folds  of  enamel.  The  dental  formula 

is  : — i  -,  c  -,  pin  .-,  m  -  .     For   our  purpose   here 
o       1          4        o 

it  is  the  molars  almost  exclusively  that  come  into 

4     2 

consideration,  hence  —  :  -  .     Thus  the  genus  Dog 
4     o 


THE  CANID^E,  OB  D0( 


261 


has  in  the  upper  jaw  four  premolars  or  teeth  that 
have  replaced  the  milk-teeth,  and  two  molars.  Of 
the  premolars  the  fourth  (p*)is  remarkable  owing 
to  its  size,  compressed  form  and  sharp  edge,  also 
by  possessing  an  inner  process  in  front ;  this  is  the 
carnassial  or  *  flesh-tooth.'  Corresponding  with  it 


FIG.  48.— Jaw  of  the  Fox.    After  Huxley. 

below  we  have  not  the  p*,  but  the  first  of  the  three 
molars  or  grinders,  m}.  The  connection  and  origin 
of  the  different  species  of  Dogs  is  determined  by 
the,  in  some  cases,  undistinguishable  shades  of 
difference  in  the  tubercles  and  processes,  by  the 

distances  of  these  points  from  each  other,  and  by 
24 


262  THE  MAMMALIA. 

the  length  and  breadth  of  the  teeth,  the  measure- 
ments of  which  have  to  be  made  by  the  tenths 
of  millimetres,  and  thus  we  finally  have  an 
animal  of  the  dog  species  of  the  present  day  not 

with        but  with  —  molars,  and   we  may  there- 
o  4 

fore  draw  the  very  probable  inference  as  to  the 
Eocene  ancestors  of  the  present  Canidae.  In  the 
above  remarks  we  have  principally  followed  an  ex- 
tremely clear  account  given  by  Huxley.1 

If  several  small  differences  are- taken  into  con- 
sideration, the  various  species  of  the  genus  Dog 
(Canis)  may  be  formed  into  two  groups,  the  one 
represented  by  the  Common  Fox,  the  other  by  the 
Brazil  fox  (Canis  azarte).  These  differences  relate 
to  the  frontal  depressions — which  are  entirely  want- 
ing in  the  fox  and  are  strongly  developed  in  the 
other  group — and  to  the  form  of  the  front  part  of 
the  brain.  By  the  side  of  the  fox  we  have  Canis 
fulvus,argentatus,  littoralis,zerda,  lagopus  and  others; 
on  the  other  hand  the  Jackals  and  Wolves,  all  varie- 
ties of  the  Domestic  Dog,  Canis  anihus,  latrans,  an- 
tarcticus,  magellanicus,  cancrivorus,  varieties  of  the 
Dingo.  In  both  groups  subdivisions  have  again  to 

1  Huxley,  ?  Cranial  and  Dental  Characters  of   the  Camel®,' 
Proc.  Zool.  Soc.,  1880. 


THE  CANID^E,   OE  DOGS.  263 

be  made  in  accordance  with  the  form  and  strength 
of  the  carnassial  tooth.  However,  even  when  a 
good  idea  of  the  Fox  and  Wolf  type  has  been  ob- 
tained, the  differences  finally  merge  one  into  the 
other,  and  thus  here  again  comes  an  end  to  all 
systematic  arrangement. 

In  all  the  above-mentioned  animals  of  the  dog 

2 

species  the  dental  formula  of  the  molars  is  -.     The 

3 

agreement  of  the  lobes,  processes,  and  tubercles  of 
the  teeth  is  such,  that  blood-relationship  appears 
certain  if  the  alternative  of  convergence  or  inherit- 
ance is  properly  considered. 

We  must  now  refer  to  the  question  of  the  origin 
of  the  domestic  dog.1  That  the  whole  line  of  foxes 
has  nothing  to  do  with  the  dog  has  long  been  an  esta- 
blished fact.  On  the  other  hand,  Darwin  endea- 
voured to  prove  that  various  wild  tribes  of  men  in 
different  parts  of  the  globe  tamed  native  wolf-like 
animals,  and  that  the  crossings  of  these  species  and 
breeding  of  various  kinds  produced  the  domestic 
dog  of  our  day.  This  opinion  of  Darwin's  has  been 
somewhat  modified  by  L.  H.  Jeitteles,  a  careful 
authority  on  the  domestic  animals.  According  to 

1  Darwin,  The  Variation  of  Plants  and  Animals  under 
Domestication ;  Jeitteles,  Die  Stammvater  unserer  Hunde-Eassen. 
Vienna,  1877. 


264  THE  MAMMALIA. 

him  the  wolf  (Canis  lupus)  has  no  connection  with 
the  European  and  west-oriental  races  of  Dogs,  the 
connection  being  mainly  through  the  Jackal  and 
the  Indian  Wolf  (Canis  pallipes).  The  races  partly 
lead  back  into  prehistoric  times.  Closest  to  the 
Jackals  we  have  the  so-called  Turf -dog,  known 
from  the  turf  deposits  of  the  lake  dwellings,  and 
which  is  probably  the  ancestor  of  our  Pomeranian 
dogs.  Allied  to  it  we  have  the  terriers  and  turn- 
spits. From  Canis  pallipes  is  descended  the  so- 
called  Bronze-Dog,  which  most  probably  came  to 
Europe  with  human  immigrants  from  Asia,  and 
with  it  the  sheep-dog  of  Central  Europe,  the  larger 
sporting  dog,  the  poodle,  cur-dog,  and  bull- dog. 
The  ancestor  of  a  third  group  may  perhaps  be 
found  in  the  large  jackal  (Canis  lupaster)  of  North 
Africa,  to  which  we  should  also  have  to  refer  the 
ancient  Egyptian  dog,  the  Oriental  street  dog,  and 
the  wild  dog  of  Africa. 

This  does  not  as  yet  settle  the  question  as  to 
which  fossil  forms  may  be  concealed  among  the 
numerous  races  of  the  domestic  dog.  Various  con- 
jectures have  been  made,  none  of  which,  however, 
are  based  upon  any  special  reasons.  According  to 
Blainville's  opinion,  a  Diluvial  species  of  a  gentle 
and  sociable  nature — no  longer  existing  in  a  wild 


THE  CANINE,  OR  DOGS.  265 

state — must  have  been  the  primeval  form  of  the 
domestic  dog ;  but  after  what  has  been  said  above, 
this  general  way  of  settling  the  question  must  be 
regarded  as  one  that  no  longer  holds  good.  Wold- 
rich's  l  views  show  a  greater  amount  of  probability, 
and  have  lately  been  taken  up  again ;  he  maintains 
that  our  domestic  races  are  descended  from  several 
wild  forms  of  the  Canidae  of  the  Diluvium,  and 
herein  he  agrees  with  what  Darwin  and  Huxley 
have  stated  regarding  the  relation  between  the 
Domestic  Dog  and  the  living  Jackals  and  Wolves. 

It  may  with  certainty  be  maintained  that  the 
direct  ancestors  of  the  European  Wolf  are  to  be  found 
in  the  Diluvial  deposits.  Formerly  a  huge  animal 
of  the  wolf  species  was  distinguished  as  the  Cave 
Wolf,  without  there  being  any  distinct  character  to 
separate  the  two  forms.  A  third  form  of  wolf — 
Canis  suessii,  from  the  Loss  near  Vienna — is  de- 
scribed as  a  slim  but  powerful  animal,  strong 
enough  even  to  pursue  and  overpower  the  larger 
species  of  plant-eaters.  It  is,  in  fact,  one  of  the 
eight  species  of  wolves  which  can  be  distinguished 
during  the  Diluvial  early  ages  of  man.  And  in 
addition  to  these  there  are  about  five  kinds  of  foxes. 

1  Woldrich,  *  Wilde  Caniden  des  Diluviums,'  Wiener  Denk- 
schriften,  1879. 


266  THE  MAMMALIA. 

In  now  returning  to  the  living  Canidse,  several 
species  demand  our  attention,  one  of  which  is 
described  as  Icticyon  venaticus,  a  native  of  Brazil, 
the  other  under  the  generic  name  of  Cyon,  inhabit- 
ing the  countries  to  the  north  and  north-east  of  the 
Altaian  mountains.  These  dogs  do  not  possess  the 
third  molar  in  the  lower  jaw,  and  the  m  in  the  upper 
jaw  is  so  small  that  a  reduction  appears  to  be  immi- 


FIG.  49. — Lower  Jaw  of  Icticyon.     After  Huxley. 

nent  there  as  well.  It  is  in  the  natural  course  of 
things  that  one  or  both  of  the  first  premolars,  or 
the  last  molar,  should  become  useless  and  forced  to 
disappear,  by  the  neighbouring  teeth  being  specially 
taken  into  requisition,  although  in  most  cases  we 
do  not  know  the  immediate  reason  of  this.1  The 

1  Any  of  our  readers  who  can  examine  the  head  of  a  dachs- 
hund may  convince  themselves  of  the  fact  that  the  first  pre- 
molar  above  and  below  can  scarcely  be  of  any  use  to  the  animal ; 


THE  CANID^E,  OR  DOGS.  267 

other  circumstances  of  the  structure  of  this  group 
do  not  lead  us  to  expect  anything  special  from  this 
concentration  of  the  dentition.  In  former  times, 
however,  as  we  shall  soon  see,  a  most  varied  develop- 
ment of  new  genera  of  Beasts  of  Prey  began  with 
dog-like  animals. 

Much  more  interesting  for  the  purpose  of  our 
investigation  here  is  the  Otocyon  lalandii,  the  spoon- 
dog  of  South  Africa,  so  called  from  the  peculiar 
formation  of  the  skull.  Its  habits  show  an  approxi- 
mation to  the  Foxes,  yet  as  regards  dentition  it  does 
not  show  this  affinity,  inasmuch  as  it  possesses 

-  :  -  molars,  and  also  shows  the  most  remarkable 
4  4 

differences  in  the  relative  size  of  the  single  teeth. 
As  already  said,  the  spoon- dog  is  in  many  ways, 
and  as  regards  dentition,  shaped  after  the  fashion 
of  the  dog  type,  and  can  thus  scarcely  be  dragged 
out  of  this  connection,  and  we  are  compelled  to 
look  upon  it  as  a  still  existing  primary  form  of  dog. 
The  whole  palaeontology  of  the  Vertebrates  shows 
that  the  many-toothedness  of  Mammals  is  an 
inheritance  from  their  lower  ancestors,  and  that 

it  is  a  little  stump  which  does  not  come  in  contact  with  the 
opposite  row  of  teeth,  and  is  frequently  wanting  altogether.  If 
the  dachshund  is  not  forcibly  suppressed  as  a  species,  its  denti- 
tion will  one  day  inevitably  be  reduced  by  one  premolar. 


268  THE  MAMMALIA. 

any  increase  of  the  teeth  within  a  class  has  prob- 
ably never  taken  place. 

o     o 

As  our  dogs,  with  their  -  :  -•    molars,   have   no 
3     3 

doubt  been  descended  from  fuller-toothed  animals, 
Otocyon  must  be  regarded  as  the  still  living 
representative  of  the  early  type  of  dog,  which  in 
other  characteristics  shows  more  affinity  to  the  fox 
family.  But  as  there  also  exist  species  of  the  group 
Canis  azara  with  very  small  frontal  depressions,  it 
is,  as  Huxley  says,  very  difficult  not  to  imagine  that 
these  too  must  be  traced  to  ancestors  of  the  Otocyon 
type.  From  this  species,  therefore,  we  should  have 
to  derive  the  two  lines  which  diverge  into  the  fox 
on  the  one  hand,  and  the  wolf  on  the  other.  We 
are  supported  in  this  view  by  the  observation  that 
the  South  American  Canis  cancrivorus  often  pos- 
sesses the  m4,  and  thus  shows  itself  to  be  another 
remnant  of  the  primary  form.  A  fourth  super- 
numerary molar  of  this  kind  is  not  a  monstrosity 
or  pathological  phenomenon,  but  an  atavism  or 
reversion  of  the  same  sort  as  the  so-called  wolfs 
tooth  in  Horses,  which  was  explained  as  a  pre- 
molar  which  existed  in  the  primary  genus  Anchi- 
therium. 

Hence  the  key  to  the  derivation  of  all  the  Dog 


THE  CANINE,   OE  DOGS.  269 

tribe  is  to  be  found  in  their  relation  to  the  spoon- 
dog.  What  Huxley  states  regarding  the  simi- 
larity between  its  dentition  and  that  of  the  lower 
bear-like  genera  is  certainly  well  worth  conside- 
ration, but  is  of  less  importance  than  the  con- 
clusion he  draws  from  a  discovery  of  his  own.  In 
several  hundred  different  species  of  Dogs  he 
found  fibrous  formations  which  are  said  to  corre- 
spond with  the  marsupial  bones  (ossa  epipubica),  the 
distinguishing  feature  of  the  Marsupial  group.  If 
this  observation  becomes  an  established  fact,  the 
direct  descent  of  dogs  from  Marsupials  would  seem 
in  the  highest  degree  probable.  However,  as  one 
of  our  first  comparative  anatomists  has  maintained, 
we  still  require  further  proofs  for  Huxley's  observa- 
tion. In  imagining  the  Dogs  connected  with  the 
Marsupials  we  should  not,  in  the  first  instance, 
have  to  consider  our  present  carnivorous  Marsu- 
pials (Thylacinus,  Dasyurus),  whose  row  of  molars 
consist  of  one  tooth  less  than  that  of  Otocyon, 

O  A 

and  are  generally  characterised  as  p  -,  m  -.      The 

4         4 

Marsupial  Eats  would  more  likely  have  to  be  taken 
into  consideration.  They  are  the  only  known 
animals  from  the  Eocene  with  four  molars.  More- 
over, by  using  the  flat  part  of  their  hands  and  feet, 


270  THE  MAMMALIA. 

and  possessing  pointed,  tuberculate  molars,  they 
point  to  the  Insectivora.  For  another  circumstance 
to  be  considered  is,  that  various  peculiarities  in  the 
teeth  of  the  lower  Canidae  show  approximation  to 
the  dentition  of  the  Insectivora ;  and  the  occurrence 
of  rudimentary  clavicles  and  the  rudiment  of  a 
fifth  toe  on  the  hind  limb,  also  clearly  point  to 
ancestors  with  well-developed  clavicles,  and  the  full 
number  of  five  toes.  All  this  is  found  united  in 
the  Insectivora :  hence  our  present  dogs  have  been 
traced  back  to  the  Eocene  and  Pre-Eocene  Insect- 
eaters  with  certain  peculiarities  of  the  Marsupials. 
This  derivation  of  the  Dog  tribe — which  is  based 
mainly  upon  deductions  from  the  present  nature 
and  distribution  of  the  group — goes  back,  therefore, 
into  that  dim  twilight  which,  in  the  opinion  of 
Cuvier  and  his  followers,  could  alone  precede  the 
dawn  of  true  light  in  the  mammal  world.  We 
shall  have  to  dwell  a  little  in  this  Eocene  period 
and  look  around  among  the  incredible  wealth  of 
mammal  forms,  which  seem,  as  it  were,  to  have  been 
re-animated  by  Filhol's  graphic  descriptions  (see 
above,  p.  64).  We  shall  obtain  some  idea  of  the 
vigour  of  that  exuberant,  plastic  life  if,  in  place  of 
the  few  Carnivora  that  are  now  inhabiting  France, 
and  indeed  Southern  and  Central  Europe,  we  ima- 


THE  CANUTE,   OE  DOGS.  271 

gine  in  one  part  of  South-western  France,  of  Carni- 
vora  alone,  some  forty  species  from  the  size  of  the 
marten  up  to  that  of  the  most  powerful  wolves  and 
bears.  They  lived,  as  the  vast  quantities  of  their 
remains  testify,  partly  in  herds ;  and  of  food  there 
was  an  abundance  in  the  corresponding  numbers 
and  varieties  of  plant-eaters. 

First  of  all  comes  the  Viverrine  Dog  (Cynodictis) , 
which,  although  possessing  the  dental  formula  of 
the  Dog 

.81          42 
tg^r,^m?m-, 

(of  which,  in  the  upper  jaw  the  fourth  premolar,  in 
the  lower  jaw  the  first  molar  stands  for  the  carnas- 
sial  tooth)  had  a  very  narrow  skull,  with  broad, 
strong  cheek-bones — an  admirably  developed  beast 
of  prey  between  the  size  of  a  fox  and  a  wolf. 
These  animals,  Filhol  says,  are  curious  and  very 
peculiar  forms,  in  which,  after  a  very  careful  ex- 
amination, certain  points  are  at  length  discovered 
by  which  they  show  affinity  with  our  present 
Carnivora.  But  in  spite  of  every  effort  to  bring 
them  under  one  head,  it  cannot  be  done.  And 
hence  we  have  to  assign  to  them  an  essentially 
distinctive  character,  a  position  outside  the  cus- 
tomary classification,  and  one,  in  fact,  which 


272  THE  MAMMALIA. 

approximates  the  living  families.  The  French 
investigator  means  to  say  that  they  are  dog-like 
animals,  but  not  dogs ;  that,  in  fact,  they  cannot 
be  classed  with  any  one  of  the  present  families 
of  Carnivora,  although  showing  the  character- 
istics of  the  class  in  the  various  parts  of  their 
skull  with  which  we  are  very  well  acquainted — the 
mid  jawbone,  gums,  alar  processes,  tympanic  bones 
— as  well  as  the  form  of  the  skull  as  a  whole.  We 
should  not  exactly  say  that  the  animals  stand  be- 
yond our  system  of  arrangement,  but  that  they  do 
away  with  existing  gaps.  This  is  most  obviously 
the  case  with  their  dentition.  In  most  of  these 
forms  of  Cynodictis — which  can  be  denned  as 
species — the  teeth  are  all  well  marked  and  developed 
according  to  their  position.  But  in  Cynodictis  inter- 
medius,  the  last  lower  molar,  m3,  is  so  small  that  it 
is  evidently  of  not  much  use,  and  we  may  rely  upon 
its  gradual  disappearance.  Were  this  to  happen 
we  should  then  have  the  dental  formula  of  the 
Viverras.  And  it  does  happen:  the  race  named 
Cynodictis  intermedius  viverroides  from  the  C.  inter- 
medius  has  become  a  Viverra. 

With  the  loss  of  that  molar  there  arises  a  small 
modification,  p*,  hence  one  connected  with  the  im- 
portant carnassial  tooth  of  the  lower  jaw;  and 


THE  CANID^E,  OE  DOGS.  273 

what  is  most  remarkable,  the  same  loss  is  met  with 
in  two  other  species  (C.  crassirostris,  leptorhynchiis), 
the  same  modification  of  the  carnassial  tooth.  It 
is  not  known  what  change  in  the  mode  of  life 
caused  these  same  changes  in  the  teeth  in  several 
different  species.  We  are  content  with  knowing  in 
what  manner  so-called  new  species  and  genera 
appear  on  our  earth ;  in  fact,  not  suddenly,  but 
by  imperceptible  shades  of  difference,  which  in- 
crease in  the  course  of  thousands  of  generations, 
until,  finally,  what  seemed  at  first  an  exception  to 
the  rule  becomes  the  prevailing  state  of  things. 
The  objection  so  frequently  brought  forward 
that  these  '  accidental '  deviations  would  always 
again  be  neutralised  by  crossings  with  unchanged 
members  of  the  species — if  geographical  isolation 
did  not  come  to  assist  them — have  no  founda- 
tion whatever;  for  our  discoveries  in  palaeonto- 
logy prove  the  contrary.  It  must  be  remembered 
that  the  expression  *  accident '  applies  only  in  so 
far  as  it  conceals  our  ignorance  of  causes  and 
occasions.  In  many  cases — for  instance,  in  the 
transformation  of  Mastodons  into  Elephants — 
we  can  with  some  certainty  determine  the  altered 
conditions  of  food  to  which  the  teeth  had  to  adapt 

themselves. 
25 


274  THE  MAMMALIA. 

And  in  the  present  case  we  have  only  to  deal 
with  an  established  fact,  that  the  Viverrce  are  the 
descendants  of  the  Viverrine  Dog,  Cynodictis. 
There  can  be  no  dispute  about  this.  Hereupon 
commences  a  new  series  of  modifications,  and  from 
the  Viverrae  are  descended  the  Weasels. 

We  now  pass  from  the  Upper  Eocene  of  the 
phosphate  of  Quercy  to  a  somewhat  later  period, 
which  produced  the  Lower  Miocene  deposits  of 
Saint  Gerard  le  Puy,  on  the  Allier.  Here  is  found 
the  Plesictis,  a  carnivorous  animal  distinguished 
from  the  Viverrae  mainly  by  the  form  of  its  head. 
Filhol  points  out  that  a  *  comb '  (crista)  of  the 
sagittal  suture  not  previously  existing,  has  been 
formed  by  a  contracting  of  the  temporal  *  combs ' 
of  the  Cynodictis;  in  other  words,  that  we 
have  the  perfectly  justifiable  conclusion  that 
smaller  species  of  Cynodictis  passed  over  into  the 
form  o.f  Plesictis  under  the  influence  of  natural 
causes. 

In  the  races  directly  descended  from  Cynodictis 
a  change  takes  place  in  the  nature  of  the  teeth,  and 
the  dentition  assumes  more  and  more  the  character 
of  that  of  the  weasel,  while,  on  the  other  hand,  the 
peculiarities  of  the  Viverrae  disappear ;  thus  the  line 
Plesictis — Stenoplesictis — Palceoprionodon  leads  in 


THE  CANID^E,   OK  DOGS.  275 

gentle  modifications  to  Mustela,  and  henceforth 
there  exist  weasels. 

Equally  distinct  are  the  intermediate  forms 
by  which  is  accomplished  the  transition  from  the 
weasel's  dentition  to  that  of  the  Cats.  The  genus 
Procelurus  appears  likewise  with  two  tuberculate 
teeth  in  the  upper  jaw  behind  the  carnassial  tooth. 
But  single  species  of  the  genus  sometimes  show  a 
loss  of  the  back  molar,  and  herein  approach  the 
cats  ;  the  back  edge  of  their  carnassial  tooth,  more- 
over, loses  a  tubercular  heel  or  process.  By  this 
small  modification  Protelurus  has  become  Pseud- 
celurus,  inasmuch  as  the  modification  was  general  and 
continued  for  some  length  of  time.  In  comparing 
the  following  statement  of  the  simplification  of  the 
molars  of  the  lower  jaw : 

Premolars  Carnassial  Tubercular  teeth 
4                         1  l—pt    m2 

4  1  0—pi    m, 

3  1  0—^3    w, 

which  have  actually  been  observed,  and  which 
shows,  moreover,  that  the  front  premolar  p2  has 
also  become  reduced — it  becomes  clear  that  the  only 
distinction  between  a  Pseudalurus  of  this  kind,  for 
example,  Ps.  Edwardsii  and  our  present  cats,  is  that 
it  possesses  a  minute  premolar.  Hence  the  great 
simplification  in  the  number  of  teeth  which  Filhol 


276  THE  MAMMALIA. 

was  able  to  establish  in  these  animals,  justifies 
the  supposition  that  this  small  piece  will  disappear 
later,  in  the  same  manner  as  has  happened 
previously  to  the  one  that  existed  in  front  of  it  (p}), 
and  had  previously  happened  to  the  tuberculate 
tooth  (?ft2).  The  genus  Felis  herewith  appears  upon 
the  scenes. 

The  concentration  of  the  dentition  did  not  re- 
main stationary  at  the  stage  acquired  by  the  cats, 

3         1 

p  - ,    m  - ;  the  highest  degree  of  specialisation  was 

attained  by  the  so-called  Sabre-toothed  tiger  (Ma- 
chairodus)  with  the  dental  formula : 

.31         20 

t  -,    c  _,   p  ~    m- 

3         12         1 

with  26  teeth  against  30  in  the  cats.  Machairodus, 
an  animal  somewhat  the  size  of  a  tiger,  possessed 
in  its  upper  jaw  a  powerful  sabre- shaped  canine 
tooth  which  projected  from  the  mouth  downwards 
extending  beyond  the  lower  jaw.  This  lower  jaw 
shows  an  indentation  obviously  produced  by  the 
pressure  of  the  huge  upper  canine  teeth  as  they 
became  more  and  more  developed  and  endeavoured 
to  make  room  for  themselves.  The  cause  of  the 
dying  out  of  this  most  definite  of  all  the  Carnivora 
of  the  period,  has  been  attributed  to  the  extra- 


THE  CANUTE,   OR  DOGS.  277 

ordinary  development  of  these  tusks,  the  length  of 
which  finally  may  have  prevented  their  opening 
their  jaws  sufficiently.  In  answer  to  this  it  can 
only  be  said  that  a  bad  hypothesis  is  better  than 
none.  The  sabre-toothed  tiger  appears  and  dis- 
appears in  the  Miocene  deposits  both  of  the  Old 
and  the  New  World. 

Pseudcelurus  was  shown  above  to  be  an  inter- 
mediate form  between  the  weasel  and  the  cat. 
This  does  not  exclude  other  intermediate  forms. 
One  of  these  is  the  Mlurogale,  also  the  size  of  a 
tiger  and  found  in  great  abundance  in  the  phos- 
phate of  Quercy.  Its  upper  jaw  resembles  that  of 
Cats,  the  lower  jaw  shows  the  teeth  of  the  Muste- 
lidae  (weasels  and  otters).  The  races  arrange  them- 
selves in  such  a  manner  that,  notwithstanding  the 
extraordinary  variations  in  the  size  of  the  teeth— 
in  those  which  deviate  most  from  the  primary 
form — the  lower  jaw  also  has  preserved  the  Cat 
formula.1 

1  We  shall  not  refrain  from  pointing  out  the  difficulty 
which  is  met  with  in  this  apparently  simple  line  of  descent. 
Of  all  the  living  Carnivora  the  Cats  possess  the  most  perfect 
rudimentary  clavicles,  the  others  have  either  smaller  traces  of 
these  or  none  at  all.  All  the  ancestors  of  the  Cats  must  at  least 
have  possessed  clavicles  such  as  are  still  met  with  in  the  Cats. 
And  it  is  quite  intelligible  that  the  clavicles  should  have  con- 
tinued to  exist  in  Cats,  owing  to  their  have  retained  the  habit  of 


278  THE  MAMMALIA. 

In   order   to  illustrate   our  remarks   we   have 
drawn  up  the  following  piece  of  pedigree  : — 

Yiverrine  dogs  (Cynodictis) 

VIVKKBJE 

I 
Plesictis 

Stenoplesictis 


Premiums  Palrooprionodon 

|  I 

Pseudtelurus  WEASELS 

CATS 

I 
Sabre-toothed  tiger 

The  above  is  the  shortest  way  of  expressing  the 
result  of  a  long  series  of  the  most  careful  com- 
parison of  facts,  and  has  as  much  right  in  claiming 
to  be  credited  as  any  other  conclusion  deduced  from 
scientific  investigations,  in  whatever  province  the 
facts  have  been  gathered.  When  it  is  admitted  that 
the  philologist  can  arrange  the  age,  connection,  and 
succession  of  manuscripts,  in  a  tabular  form,  from 
the  character  of  the  writing,  from  the  use  of  signs 

climbing,  while  in  the  other  animals  they  would  become  more 
and  more  reduced.  Naturally  enough  we  do  not  know  the 
particulars  connected  with  this  reduction.  But  should  we  suc- 
ceed in  establishing  the  want  or  a  greater  reduction  of  the 
clavicle  in  one  of  the  branch  families  in  the  above  pedigree 
(arranged  according  to  the  development  of  their  dentition)  our 
whole  arrangement  would  of  course  collapse. 


THE  CANINE,   OR  DOGS.  279 

and  word-forms,  &c.,  and  that  the  literary  historian 
may  conclude  that  a  certain  work  was  written  by 
a  certain  author,  from  the  style  of  the  composition 
and  certain  modes  of  expression,  &c. ;  and  further, 
when  it  is  admitted  that  a  lawyer,  by  the  com- 
bination of  passages,  all  of  which  are  obscure,  can 
throw  light  upon  a  case  of  Eoman  law,  then  I 
maintain  our  procedure  also — a  zoologico-palse- 
ontological  method  of  investigation  and  drawing 
conclusions — must  be  granted  as  a  matter  of 
course. 

The  descent  of  Weasels  and  Cats  from  those 
changing  forms  of  Cynodictis,  therefore,  presents  a 
great  degree  of  probability  but  no  actual  certainty ; 
for  different  animals  that  appear  geologically  almost 
as  contemporaries,  may  occur  parallel  with  one 
another  with  precisely  similar  dental  formulas  and 
reductions  in  the  jaw.  However,  we  come  to  the 
certain  conviction  that  the  transformations  actually 
took  place,  and  that  our  present  animal  could  and 
must  have  originated  in  that  natural  manner. 
And  as  it  is  mainly  our  wish  merely  to  pave  the 
way  for  this  opinion,  it  will  be  almost  superfluous 
to  enter  any  more  fully  into  the  primary  and  tran- 
sition forms  between  the  present  and  the  primeval 
Carnivora. 


280  THE  MAMMALIA. 

It  may,  however,  be  remarked  that  our  B  ars 
had  representatives  in  the  Miocene.  In  those  times 
there  existed  the  Ampliicyon,  of  the  size  of  a  wolf, 
but  in  reality  a  dog  with  p*,  m3,  the  broad  crowns 
of  the  first  two  molars  showing  the  incomings  of 
tubercles  which  point  to  a  definite  form  of  food. 
This  characteristic  is  even  more  marked  in  a  later 
form  of  bear-dog,  Hyanarctos  (p*y  m2),  and  has 
preserved  its  full  development  in  the  bear  (Ursus) 
from  the  Pliocene  up  to  the  present  period.  How- 
ever, the  fewer  number  of  teeth  of  the  Hysenarctos 
again  forbids  its  being  classed  with  the  actual 
ancestral  line  of  the  Bears.  The  latter  with  their 
flat  tuberculate  molars,  which  point  to  a  fixed  food, 
and  their  tolerably  blunt  carnassials,  are  compara- 
tively a  late  modification,  to  a  certain  extent  a 
reversion  to  the  beast  of  prey.  This  character 
has,  however,  been  retained  by  the  polar  bear, 
which  has  again  become  a  pure  flesh-  and  fish- 
eater. 

Gaudry  has  pointed  out  an  ancestor  for  Hyaenas 
in  the  genus  Ictitherium  from  among  the  fauna 
discovered  at  Pikermi.  All  that  was  required  in 
this  animal  to  give  its  dentition  the  formula  and 
structure  of  that  of  the  Hyaena,  was  the  disappear- 
ance of  the  second  molar  above  and  below  (and  the 


THE  CANID^E,   OR  DOGS.  281 

upper  one  already  shows  signs  of  reduction),  also 
an  extremely  small  difference  in  the  carnassial 
tooth.  Indications  even  existed  in  the  Ictitherium 
of  the  peculiar  strength  of  the  premolars  of  our 
present  hyaenas,  which  show  a  predilection  for 
gnawing  and  crunching  bones.  Animals  of  the 
Viverra  type  seem  to  have  been  the  ancestors  of 
this  branch. 

In  the  Lower  Eocene  strata  of  Europe,  but  more 
particularly  in  the  corresponding  deposits  of  North 
America,  numerous  Carnivora  have  been  found 
which  differ  more  from  the  living  families  than 
most  of  the  fossil  genera  that  were  brought  into 
connection  with  them  above,  and  which,  moreover, 
can  be  brought  into  this  connection,  although, 
taken  as  a  whole,  they  prove  to  be  but  the  first 
stages  of  very  highly  developed  beasts  of  prey  from 
the  Upper  Eocene.  The  characteristic  which  most 
distinctly  indicates  the  low  position  of  the  Early 
Eocene  beasts  of  prey,  is  the  small  development  of 
their  brain,  which  is  known  to  us  from  the  form  of 
the  skull,  and  from  natural  fillings  and  castings.  In 
their  case  the  olfactory  lobes  appear  as  broad  pro- 
cesses of  the  fore  end  of  the  larger  division  of  the 
brain,  the  mid-brain  being  scarcely  covered  by  it, 
the  back  part  not  at  all.  As  regards  Europe,  the 


282  THE  MAMMALIA. 

Arctocyon  (Palceocyon  blainville) l  has  long  since 
been  known  as  an  animal  with  a  brain  approaching 
that  of  the  Marsupial  type  ;  whereas  its  dentition, 
which  resembles  the  earlier  form  of  pig-shaped 
animals,  Entelodon,  points  to  the  Omnivora,  while  it 
has  also  something  of  the  bear  as  a  flesh-eater. 
Further,  we  must  mention  the  Hycenodon  and 
Pterodon,  so  often  referred  to,  and  usually  denned 
as  *  mixed  forms  ' ;  they  appear  somewhat  later,  it 
is  true,  but,  nevertheless,  show  resemblances  to  the 
Marsupials — for  instance,  in  the  form  of  their  teeth 
they  are  closely  allied  to  the  Thylacinse,  though  not 
as  regards  their  change  of  teeth. 

With  these  animals — which  are  partly  also 
found  in  America — Cope  classes  a  whole  series  of 
American  genera  of  doubtful  position  mostly  from 
the  Eocene  ;  he  gives  them  the  name  of  Creodonta, 
and  regards  them  as  the  ancestors  of  the  subsequent 
Carnivora  proper.  In  their  case  the  row  of  molars 
is  not  separated  definitely  by  a  carnassial  tooth,  or 
but  imperfectly  so  :  the  jaws  are  lengthened,  and 
the  muscles  for  chewing  are  placed  in  such  a  man- 
ner that  only  a  smaller  degree  of  power  can  be 
developed  than  in  the  subsequent  true  Carnivora ; 

1  Lemoine,     'Recherches     sur    les    ossements    fossiles    des 
environs  de  Reims,'  Annales  des  sciences  nat.,  1879. 


THE  CANID^E,  OR  DOGS.  283 

these  latter,  by  the  shortening  of  their  jaw  and  the 
reduction  of  their  dentition,  were  all  the  better  able 
to  overpower  their  prey. 

One  of  the  most  important  forms  of  these  Creo- 
donta — because  extremely  numerous  in  New  Mexico, 
and  found  in  three  species  in  the  phosphate  of 
Quercy — is  Oxycena.  The  species  vary  in  size 
between  a  badger  and  a  jaguar.  The  dental  for- 
mula is  :  i  -,  c  i,  pm  -,  m  -.  Herein,  therefore, 

the  Eocene  fauna  of  the  Old  and  the  New  World 
again  show  connection. 

We  are  the  less  inclined  to  enter  upon  an 
account  of  the  five  families  of  Creodonta,1  because 
the  grouping,  the  assumed  connection,  and,  above 
all,  the  derivation  of  our  present  large  group  of  Car- 
nivora,  the  dogs  and  cats,  often  seem  to  be  in  want 
of  those  safe  foundations  pointing  from  case  to 
case,  from  genus  to  genus,  which  Filhol's  investi- 
gations and  deductions  have  made  so  incontestable. 


In  order,  however,  to  give  those  of  our  readers 
specially  interested  in  the  subject  some  suggestions 
for  further  enquiry,  we  may  here  mention  the 

1  Arctocynoidse,   Miacidee,   Oxytenidae,  Amblyctonidae,  Meso- 
nychidae. 


284  THE  MAMMALIA. 

systematic  relationship  into  which  Cope  '  has  place 
the  Creodonta. 

The  mammals  from  the  Wasatch  beds  of  Utah 
and  of  New  Mexico  have  been  divided  into  fifty- 
four  species,  most  of  which  are  distinguished  by  a 
very  small  and  evidently  low  form  of  brain,  to 
judge  from  the  structure  and  position  of  its  pa,rts. 
That  of  Corypliodon  (Fig.  14)  appears  almost  like 
that  of  a  reptile,  and  in  this  character  the  Hoofed 
and  Clawed  Animals  agree.  They  also  agree  in  the 
structure  of  their  joints,  the  different  parts  of  their 
limbs,  and  also  in  the  number  of  their  toes,  of 
which  five  were  observed  in  from  forty-one  to  fifty- 
four  species.  In  the  flesh- eaters  there  is  no  car- 
nassial  tooth;  in  the  plant-eaters  no  teeth  with 
crescentic  crowns ;  all  the  molars  belong  to  the 
type  of  tuberculate  teeth,  either  in  primitive  sim- 
plicity, or  of  that  form  where  the  tubercles  are 
compressed  to  the  side,  and  coalesce  into  imperfect 
transverse  ridges.  On  this  account  the  animals 
have  been  named  Bunotheria,  and  are  arranged  in 
the  following  manner : — 

Insectivora,  Treniodonta,  Tillodonta,  Creodonta,  Mesodonta 
Bunotheria. 

There  can  be  no  doubt  that  these  Early  Eocene 

1  See  p.  72,  note. 


THE  CANIDJE,   OR  DOGS.  285 

animals — owing  to  the  above-mentioned  peculiari- 
ties— show  a  certain  necessity  for  being  classed 
together,  and  it  is  self-evident  that  they  must  stand 
nearer  to  one  another,  were  it  only  on  account  of 
the  smaller  period  of  time  since  their  separation 
from  the  primary  stock,  which  must  be  assumed  to 
have  been  common  to  them  all.  However,  in  our 
opinion,  the  characteristics  specified  above  go  no 
further  than  to  indicate  a  most  general  form  of  con- 
nection. When  Cope  maintains  that  the  different 
groups  of  Bunotheria  are  related  to  one  another, 
somewhat  in  the  same  way  as  are  the  orders  of 
Marsupials,  it  seems  to  us  that  this  scarcely  applies 
to  the  case.  To  give  an  example  :  what  has  Tillo- 
therium  from  the  Eocene  of  Wyoming  (Fig.  50)  in 
common  with  the  flesh-eaters  Arctocyon  and 
Oxycena?  By  the  smallness  of  its  brain  most 
certainly  nothing ;  nor  by  its  five  toes,  and  the  cir- 
cumstance that  the  whole  sole  of  the  foot  is  applied 
to  the  ground.  The  resemblances  in  the  molars  are 
not  remarkable,  while  the  decidedly  rodent- like  form 
of  the  incisors  only  proves  the  peculiarity  of  the 
animal.  Any  typical  feature — such  as  the  marsupial 
pouch  or  the  marsupial  bones,  or  the  openings  of 
the  urinary  and  genital  organs  peculiar  to  the  Mar- 
supials— is  not  met  with  in  any  of  these  animals, 
26 


286  THE  MAMMALIA. 

as  far  as  can  be  judged  from  the  often  great  paucity 
of  their  remains. 

Only  one  point  stands  out  in  this  attempt  to 
throw  light  upon   the   relationships   between   the 


FIG.  50.     Skull  of  Tillotherium  fodiens,  from  above.    One-fourth 
nat.  size.    After  Marsh. 

mammals  of  that  early  period;  the  indrawing  of 
the  Insectivora,  of  that  type  which  has  been  pretty 
faithfully  preserved  from  the  earliest  traces  of 


THE  SEALS.  287 

Marsupials  or  Insectivora  in  the  Trias  down  to  the 
present  day,  and  which  seems  to  have  gradually 
sent  out  off-shoots  in  the  most  different  directions, 
till  at  length  they  became  unrecognisable. 

9.    THE    SEALS. 

According  to  the  form  of  their  skull,  dentition, 
and  mode  of  life,  Seals  are  '  carnivorous  animals 
that  have  adapted  themselves  to  a  life  in  water,' 
and  in  this  way  they  are  generally  described.  In 
order  to  make  the  theory  acceptable,  it  is  customary 
to  point  to  our  Sea-otter,  which,  unlike  its  nearest 
relative  that  thirsts  for  warm  blood,  has  become  a 
pure  fish-eater.  The  Sea-otter  uses  its  hind  limbs 
after  the  manner  of  seals,  and  its  skull  shows  a 
depression  of  a  similar  kind  to  that  which  has 
proved  advantageous  to  the  Seals.  Hence,  so  it 
is  said,  we  have  to  imagine  the  ancestors  of  the 
Seals  on  that  line  which  has  led  them  farther  and 
farther  from  their  original  forms,  which  very  gra- 
dually changed  their  limbs  into  fin- shaped  rudders 
(while  perfectly  retaining  the  pelvis  and  the  articu- 
lation of  the  skeleton),  and  whose  skull  became  a 
light,  thin-walled  box  not  burdened  with  strong 
teeth.  Only  the  Walrus  (Trichechus)  has  developed 
a  couple  of  heavy  tusks,  corresponding  with  its 


288  THE  MAMMALIA. 

entirely  different  mode  of  life,  inasmuch  as  it 
burrows  in  the  ground  for  certain  kinds  of  mussels. 
All  the  others  hunt  for  fish,  which  they  can  readily 
tear  to  pieces  with  their  sharp  canine  teeth  and 
pointed  molars,  which  are  compressed  somewhat  to 
the  side. 

Of  fossils  that  might  illustrate  the  gradual  in- 
coming of  Seals  there  are  none.  We  conclude  that 
the  process  must,  at  one  time,  have  begun  with 
carnivorous  land-animals.  The  idea  that  the  re- 
verse might  have  been  the  case  by  their  having,  as 
sea-animals,  taken  to  a  life  on  land,  has  as  little 
value  here  as  in  the  case  of  the  Cetaceans,  which 
are  mammals,  and  have  never  been  anything  else. 
The  period  during  which  they  changed  their  element 
lies  at  an  immeasurable  distance  in  the  far  past, 
but  is  probably  less  distant  than  that  in  which  the 
ancestors  of  the  whales  took  to  the  sea  while  re- 
ducing their  hind  limbs. 

There  can  be  no  question  about  making  the 
Whales  (of  course  only  the  toothed  group)  the 
primary  parents  of  the  Seals.  If  any  comparison  of 
the  kind  is  thought  of,  the  Eocene  Zeuglodonta  could 
alone  be  taken  into  consideration.  But  even  these 
latter  do  not  show  any  points  of  connection ;  their 
skull  would  have  to  be  retro-metamorphosed  to  form 


THE  SEALS.  289 

the  skull  of  the  seal,  and  their  dentition  would  have 
to  be  fuller ;  hence  the  supposed  points  of  connec- 
tion would  be  confined  to  a  superficial  resemblance 
in  the  crowns  of  the  molars,  as  there  was  very 
probably  an  essential  difference  in  the  formation 
of  the  hind  limbs. 

As  we  are  absolutely  without  any  clue  to  the 
origin  of  Seals,  we  may  here  mention  one  other 
circumstance  which  seems  to  speak  in  favour  of 
the  great  age  of  this  side-branch  of  the  primary 
Carnivora.  What  we  yet  know  of  the  change  of 
teeth  in  Seals  shows  that  the  change  takes  place  at 
an  extraordinarily  early  stage  of  life.1  In  most 
cases  the  change  takes  place  before  birth ;  the  milk- 
teeth  never  come  to  be  of  any  use  whatever,  and  the 
permanent  teeth  are  cut  when  the  young  animal  is 
but  a  few  weeks  old,  and  while  making  its  first 
feeble  efforts  to  join  its  parents  in  their  repasts. 
Fig.  51  shows  the  teeth  of  a  probably  still  unborn 
Greenland  seal  (Phoca  gronlandica).  The  shading 
shows  the  limit  of  the  gums.  It  will  be  seen 
that  the  milk-teeth  have  already  vanished,  all  but 

a   few  unimportant    remains;    d  ^   have   wholly 

1  J.    Steenstrup,    '  Maelkestandsaettet    hos     Bemmesaelen,* 
Naturhistorick  Foreningens  Vidensk.  Meddeleser.  1880. 


290 


THE  MAMMALIA. 


disappeared,  the  first  and  only  permanent   molar 
of  the  lower  jaw  has  already  cut  the  gum. 

Teeth  of  the  same  kind  as  these  milk-teeth, 
which  are  wholly  without  any  significance  to  the 
individual  as  functional  organs,  but  of  the  highest 
interest  for  the  history  of  the  group,  we  became 
acquainted  with  when  discussing  the  Whales  (p.  247). 


FIG.  51.—  Foetal  Teeth  of  a  Greenland  Seal. 

The  embryonal  teeth  of  the  Whalebone  whales— even 
though  there  were  no  Dolphins  or  Sperm  whales — 
are  an  irrefutable  proof  that  the  Whalebone  whales 
are  descended  from  toothed  animals.  In  the  same 
way  the  case  before  us  shows,  that  the  milk-teeth 
of  Seals  which  have  in  our  day  become  of  utter 


THE  SEALS.  291 

insignificance  to  the  organism,  were  of  actual 
service  to  their  ancestors,  just  as  the  deciduous 
teeth  of  most  of  our  present  mammals  are  of  use  for 
several  years.  None  of  these  milk-teeth  have  the 
prospect  of  being  preserved  like  the  one  remaining 
deciduous  tooth  of  the  Marsupials  (p.  94) ;  accord- 
ingly the  Seals  of  future  periods  will  undoubtedly 
not  show  a  trace  of  milk-teeth. 

The  Seals  belong  to  the  physically  weaker  groups 
of  mammals,  and  it  is  certainly  most  remarkable, 
and  as  yet  not  explicable,  that  the  other  mammals 
also,  which  have  already  been  discussed,  and  are 
allied  to  the  Seals  as  regards  the  suppression  of  the 
change  of  teeth,  belong,  on  the  whole,  to  the  less 
favoured  or  less  strongly  developed  orders.  For, 
as  we  have  repeatedly  remarked,  the  main  feature 
that  runs  through  the  whole  world  of  mammals  is 
the  concentration  of  strength  upon  a  shortened 
jaw,  at  the  cost  of  the  disappearance  of  teeth.  This 
is  most  evident  in  the  case  of  true  Carnivora,  where, 
however,  the  milk-teeth  still  play  an  important  part. 

10.    THE    INSECTIVORA,    OR   INSECT-EATERS. RODENTIA, 

OR   RODENTS. CHEIROPTERA,    OR    BATS. 

Of  these  three  orders  the  Insect-eaters  have 
already  been  mentioned  from  time  to  time.  They 


292  THE  MAMMALIA. 

existed  in  very  early  times,  and  had,  at  the  begin- 
ning of  the  Tertiary,  already  attained  a  stage  of 
development  which  has  been  transmitted   to  the 
present  members  of  the  group,  with  but  trifling 
modifications;  and  it   is   probable  that   a  transi- 
tion  into   hoofed    and   carnivorous   animals    had 
shown  signs  of  incoming  as  early  as  the  so-called 
Mesozoic  period.     The  question  as  to  why  all  the 
group  did   not  join   in   the   transformation   is   as 
obvious  as  the  answer  to  all  similar  questions :  that 
the  special   conditions   of   life   for   these  animals 
must  have   existed  uninterruptedly,  and  that,  in 
addition,  they  possessed  a  great  amount  of  adap- 
tability.   Thus  we  find  the  order  of  Insect-eaters — 
which  is  represented   in  Central  Europe  only  by 
the  hedgehog,  mole,  and  shrew,  but  more  numer- 
ously in    other    parts — in   many   ways   similarly 
adapted  to  the  most  varied  conditions  of  existence 
as  the  Kodents.     In  fact,  their  variability,  even  in 
primeval  times,  explains  the  fact  of  their  having 
been   able  to   adapt    themselves   to   entirely  new 
organisations,  and  Huxley  specially  traces  to  them 
the  hoofed  and  carnivorous  animals. 

The  same  remarks  apply  to  the  Rodents,  except 
that  in  all  of  the  periods  known  to  us  through 
fossils,  they  were  far  more  numerously  represented. 


INSECT-EATERS,  RODENTS,  AND  BATS.  293 

The  Rodent  type  is  likewise  found  perfected  at  the 
beginning  of  the  Tertiary  period.  It  may  be  said 
that  it  was  then  less  specialised,  that  most  of  the 
Rodents  of  those  days  were  more  carnivorous  than 
the  majority  of  our  day,  or,  at  least,  more  omni- 
vorous ;  however,  little  is  to  be  gained  from  this  for 
our  present  enquiry. 

The  dentition  of  the  Rodents  appears  to  be 
prepared,  and  almost  perfectly  attained,  by  the 
Marsupials ; l  and  thus  in  following  their  tracks 
we  are  again  referred  to  the  Jura  period,  and  even 
further  back,  where  the  separation  of  an  already 
developed  mammalian  fauna  had  taken  place :  into 
Marsupials  (as  the  main  group),  Rodents,  and 
Insect-eaters. 

The  latter  order,  no  doubt,  gave  rise  to  the  Bats, 
which  have  fluttered  about  in  their  present  shape 
since  the  Eocene  period.  Two  of  our  most  common 

1  A  comparison  of  the  very  different  shapes  of  the  molars  in 
the  Rodents  among  one  another,  and  the  approximation  of  many 
of  the  genera — not  as  yet  decided  Rodents — to  the  Rodent  type 
(for  instance,  the  wombat,  the  fingered-animal,  and  rock  coney) 
renders  it  extremely  probable  that  even  our  present  Rodents  are 
not  of  one  and  the  same  origin.  '  The  fact  remains,  animals  of 
different  derivation  have  attained  a  similar  exterior,  succeed 
extremely  well  in  the  struggle  for  existence,  or  even  better  in 
their  endeavour  to  obtain  food.  Unlike  as  they  may  be,  in  one 
point  they  are  incontestably  alike,  i.e.  in  the  development  of 
continuously  growing  incisors.' — BAUME. 


294  THE  MAMMALIA. 

genera,  Vespertilio  and  Rhinolophu*,  were  contem- 
poraries of  the  Palseotheridse  and  the  Cynodictis  of 
South-western  France.  As  regards  their  origin  we 
can  only  confess  our  ignorance  on  the  subject,  even 
though  we  can  perfectly  well  imagine  the  transfor- 
mation of  a  climbing  insect-eater  into  a  flying  one. 
The  elongation  of  the  fingers  of  the  fore  limb,  and 
the  expansion  of  the  flying  membrane  to  the  hind 
limbs,  took  place  in  those  early  periods  from  which, 
as  far  as  our  knowledge  of  the  Mammalia  is  con- 
cerned, only  a  few  dim  rays  of  light  have  found 
their  way  to  us. 

11.    THE   PROSIMI^E,    SEMI-APES. — SIMLE,    APES. 
THE    MAN    OF    THE    FUTURE. 

The  opinion  of  zoologists  of  the  Linnsean  school, 
and  those  belonging  to  the  first  half  of  our  century, 
that  the  whole  class  of  Semi- apes  were,  in  fact,  half 
apes  has  generally  been  abandoned ;  the  opinion 
was  based  upon  the  occurrence  of  hands  on  the  fore 
and  hind  limbs,  upon  the  formation  of  the  face,  and 
upon  the  peculiar  dentition,  which  in  most  cases 
shows  no  gaps.  The  more  recent  theory  does  not  ex- 
clude the  supposition  that  among  the  very  differently 
formed  genera  of  so-called  Semi-apes,  one  or  other 
species  might  claim  a  closer  relationship  with  the 


SEMI-APES  AND   APES.  295 

Apes,  but  neither  the  result  of  any  anatomical  or 
palaeontological  investigation  allows  us  to  draw 
even  a  plausible  inference  of  any  such  probability. 

As  there  are  only  a  small  number  of  genera  of 
Semi-apes,  and  these  are  confined  to  Madagascar 
(Africa  and  Southern  Asia  possess  only  a  few  aber- 
rant members  of  the  group),  we  had  to  conclude 
that  they  are  but  the  remnant  of  a  group.  Their 
dentition  and  brain  point  to  thelnsectivora,  of  whose 
morphological  capacities  we  have  had  such  important 
instances  in  the  course  of  our  discourse. 

A  true  semi-ape — and,  as  regards  skull  and 
dentition,  a  lemur  of  our  day — was  discovered  by 
Filhol  among  the  varied  accumulation  of  mammals 
in  the  phosphate  of  Quercy,  and  was  named  Ne- 
crolemur  antiquus.  '  By  its  side  there  lived  several 
species  of  a  genus  already  discovered  by  Cuvier,  the 
Adapis,  an  animal  whose  dentition  points  to  a  re- 
lationship with  the  Pig-shaped  tribe,  but  still  may 
have  been  a  creature  of  arboreal  habits.  Another 
animal  has  had  its  position  assigned  to  it  by  the 
name  of  Cebochcerus,  i.e.  Hog-ape,  owing  to  its 
very  characteristic  molars,  the  crowns  of  which 
show  four  tubercles.  America  has  also  furnished 
its  contingent  to  this  group,  which  combines  the 
characteristics  of  the  thick-skinned  animals  with 


296  THE  MAMMALIA. 

those  of  semi-apes,  a  combination  which  has  not 
shown  much  capacity  for  resistance  or  of  adapta- 
bility to  new  conditions  of  life. 

That  forms  of  this  kind  gave  rise  to  the  Apes  has 
been  conjectured  by  different  palaeontologists  and 
also  by  Gaudry.  The  Apes  found  in  the  Miocene 
of  the  Old  World  belong  already  partly  to  the  still- 
existing  group — we  dare  not  say  family — and  have 
been  called  '  AnthropomorphaB '  (man-like  apes) 
owing  to  various  peculiarities  in  different  genera. 
If  we  hold  by  the  present  arrangement  of  the 
order,  and  agree  to  the  opinion — based  upon  facts 
that  have  never  seriously  been  doubted,  and  are 
founded  upon  substantial  reasons  in  the  history  of 
the  individual  development  as  well  as  of  anatomy — 
that  the  apes  of  to-day  form  a  kindred  unity,  other 
considerations  will  present  themselves.  It  is  true 
that  lowest  species  of  South  American  apes,  the 
clawed  apes,  have  thirty-two  teeth  like  those  of  the 
Eastern  hemisphere,  but  the  form  of  these  teeth  and 
the  structure  of  the  hands  and  feet  point  to  a 
decidedly  close  proximity  with  the  Insectivora. 
Further,  they  are  allied  to  the  Apes  of  the  New 
World  by  the  fact  that  they  do  not,  like  the  Apes 
of  the  Old  World,  possess  two,  but  show  three 
premolars.  And  all  the  other  American  apes  show 


SEMI-APES  AND  APES.  297 

f*         r*  K         K. 

cheek-teeth,   not          '.     Even  the   earliest 
6 — 6  5 — 5 

Miocene  apes  of  Europe  and  Asia  show  a  reduction 
in  the  dentition,  hence  the  American  apes  stand 
nearer  to  the  primary  forms.  Further,  the  genera 
with  six  cheek-teeth,  it  seems  to.  us,  point  more, 
probably  to  ancestors  of  the  Insectivorous  species 
than  to  the  Pachyderma.  It  is,  therefore,  not 
only  possible,  but  has  come  to  seem  probable,  that 
our  present  apes,  in  regard  to  their  descent,  have 
met  from  two  entirely  distinct  origins  :  the  American 
group  from  the  Insectivora,  the  Europe- Asiatic  line, 
with  the  Anthropomorphse,  from  ancestors  of  the 
Pachydermata  species. 

This  would  lead  up  to  the  question  as  to  whether 
our  own  ancestors  belonged  to  the  thick-skinned 
group.  But  the  very  title  of  our  book  withholds  us 
from  entering  upon  this  subject,  and  we  are  all 
the  more  justified  in  postponing  any  such  discussion, 
as  the  study  of  anthropology  can  in  no  way  boast 
of  having  made  any  definite  progress  during  the 
last  ten  years.1 

1  The  relation  between  the  Anthropomorphoid  Apes  and  Man 
has  been  admirably  discussed  by  Hartmann,  *  Die  mensch- 
ahnlichen  Affen.,'  Internat.  wissenschaft.  Bibliothek,  60  Bd. 
Leipzig,  1883.  For  further  accounts  of  this  subject  we  would 
refer  the  reader  to  Schlosser  and  Seler,  Die  ersten  Menschen  und 
27 


298  THE  MAMMALIA. 

However,  we  may  be  permitted  to  cast  a  glance 
at  the  future.  Our  discussion  has  repeatedly 
proved  that  any  advance  in  the  animal  groups  was 
connected  with  a  reduction  of  the  jaw  or  of  the 
limbs.  It  would  seem  that  any  reduction  in  the 
.  fingers  or  toes  of  the  human  hand  or  foot  would  be 
neither  desirable  nor  advantageous  in  any  way; 
moreover  no  such  loss  is  to  be  feared,  although  it 
may  be,  as  Darwin  says,  that  baldness  is  in  prospect 
for  men  of  the  English  race.  It  is  a  different 
matter  as  regards  our  dentition,  and  we  are  not 
so  certain  of  its  continuing  in  its  present  state, 
although  the  human  race  would  seem  to  have  com- 
menced with  it  as  it  is,  and  found  it  sufficient  for 
the  most  varied  conditions  of  existence.  But  never- 
theless a  few  gentle  warnings  seem  to  shake  the 
belief  in  this  supposed  unalterable  stability. 

The  alternative  as  to  whether  Man  was  created 
or  developed  can  no  longer  be  raised,  now  that  we 
are  exercising  the  free  use  of  our  reason.  Man's 
dentition  has  to  be  judged  from  our  experiences 
made  in  the  mammalian  group.  Hence,  first  of 
all,  it  is  a  reduced  dentition.  True,  we  do  not 
know  the  definite  stages  by  which  it  was  attained 

die  prahistorischen  Zeiten.    According  to  a  work  of  the  same 
name  by  the  Marquis  de  Nardaillac.     Stuttgart,  1884. 


SEMI- APES  AND. APES.  299 

in  Man,  any  more  than  we  do  in  the  case  of  the 
Anthropomorphoids  and  all  the  other  Apes  of  the 
Old  World,  but  we  shall  not  hesitate  to  maintain 
that  the  ancestors  of  Man  possessed  a  fuller  number 
of  teeth,  as  long  as  deductions  are  justified  from  the 
observation  of  facts.  Our  teeth  have  decreased  in 
number  during  the  course  of  our  geologico-zoolo- 
gical  development ;  we  have  lost  on  either  side, 
above  and  below,  two  incisors,  two  premolars,  and 
one  molar.  By  this  we  transfer  ourselves  back  to 
those  periods  from  which  the  jaw  of  the  Otocyon 
has  been  preserved  (see  p.  267).  Baume,  our 
eminent  odontologist,  in  a  recent  work  which  we 
have  repeatedly  referred  to,  has  successfully  fol- 
lowed and  pointed  out  cases  of  atavism  or  reversion 
in  the  human  jaw,  by  tracing  cases  of  *  surplus ' 
teeth— and  certain  dental  formations  met  with  in 
the  jaws  in  a  large  percentage  of  cases — back  to 
those  portions  of  the  jaw  in  the  animal  ancestors 
of  Man  which  have  disappeared  in  the  course 
of  ages. 

If,  in  former  times,  more  teeth  were  met  with  in 
the  group  which  was  perfecting  itself  into  Man,  we 
must  be  permitted  to  ask — nay,  we  are  compelled  in 
a  purely  scientific  spirit  to  ask — whether  things 
have  come  to  a  standstill  in  this  part  of  our 


300  THE  MAMMALIA. 

organisation,  or  whether  a  further  reduction  is  to 
be  anticipated  ?  Man  is  certainly  one  of  the  so- 
called  '  persistent  species,'  but  he  is  not  uncon- 
ditionally stationary.  He  varies  as  regards 
dentition.  Imperfect  as  are  our  statistics  on  this 
point,  this  much  is  certain,  that  the  cases  of  dis- 
appearance or  loss  of  teeth  most  frequently  concern 
the  so-called  wisdom  teeth  and  then  the  outer 
incisors.  We  do  not  of  course  know  how  often  the 
question  has  applied  to  the  actual  and  complete  loss 
of  the  teeth,  or  only  to  some  interference  with  the 
teeth  cutting  the  gum,  occasioned  by  a  limitation 
of  the  necessary  space.  However,  it  must  be  re- 
membered that  the  shortening  of  the  jaw  stands  in 
direct  correlation  with  the  reduction  of  the  den- 
tition. A  prediction  of  the  Man  of  the  Future  is 
given  us  by  Cope :  the  lower  races  of  men  will 

retain  the  dentition  of  the  present  day,  i   -,  c  -, 

2       1 

2         3 

p  •-,  m  --,   while   the    intellectually  higher    races 
2         o 

will  be  distinguished  by  the  dental  formulas  : 

f  2>    C  I'  P  I'  m  § 
and  i  J,    c  £,   p  |,  m  |. 


THE  MAN  OF  THE  FUTURE.  301 

We  agree  with  this  in  so  far  that,  as  a  rule,  the 
reduction  of  the  dentition — where  the  disappearance 
does  not  affect  the  whole  set  of  teeth— can  be  brought 
into  connection  with  the  idea  of  progress,  and  many 
proofs  of  this  have  been  given  in  the  course  of  our 
discussion.  Still  this  higher  faculty  of  resistance 
and  of  acquiring  food  is  not  necessarily  accom- 
panied by  an  increase  in  the  power  of  the  adapta- 
bility and  a  perfecting  of  the  intellectual  faculties. 
In  the  Cat  we  have  a  more  powerful,  and  hence  a 
higher  development  of  the  nature  of  the  rapacious 
animal  than  in  the  Dog,  with  its  more  old-fashioned 
form  of  dentition.  Yet  who  would  think  of  placing 
Cats  as  intellectually  higher  than  Dogs  ?  It  is 
the  same  with  the  prospects  of  the  human  races. 
Modifications  in  the  human  dentition  are  sure  to 
take  place,  as  surely  as  man  cannot  rid  himself  of 
his  animal  ancestors,  even  though  they  may  be  felt 
to  be  inconvenient.  But  progress  in  the  intellectual 
and  moral  domain — and  here  our  well-founded 
idealism  steps  in — is  not  dependent  upon  the 
possession  or  the  loss  of  our  wisdom  teeth.  The 
correlation  is  not  wanting,  but  it  makes  itself  felt 
in  an  opposite  direction.  The  man  who  is  engaged 
in  making  inventions  and  in  scientific  pursuits,  and 
is  advancing  and  encouraging  all  the  nobler  and 


302  THE  MAMMALIA. 

more  refined  enjoyments  of  life,  is  not  improving 
the  instruments  for  the  acquisition  of  his  food ; 
they  deteriorate  in  his  hands — a  condition  which 
first  began  to  make  its  appearance  with  the  inven- 
tion of  cooking.  The  reduction  of  the  human 
dentition — which  has  been  of  advantage  to  the 
species  in  its  struggle  for  existence — has  further 
increased  and  changed  to  a  kind  of  atavism  or 
reversion,  since  reason,  acquired  with  speech,  has 
made  Man  more  and  more  independent  of  the  direct 
effects  of  his  natural  surroundings. 

Hence  it  is  not  merely  from  a  purely  zoological 
point  of  view  that  an  inference  is  formed  regarding 
the  future  change  of  the  human  race.  Moreover, 
we  cherish  the  hope — which  is  justified  by  scientific 
experiences — and  the  belief,  which  rests  upon  the 
same  foundation,  and  these  convince  us  of  the 
sure  advance  of  humanity,  and  of  the  gradual  and 
general  diffusion  of  morality,  culture,  and  well- 
being  among  the  various  races  of  Man. 


INDEX. 


ACE 
ACERATHEKIUH,  81,  190,  195 

Adapis,  295 

^lurogale,  277 

Amblyctonidae,  283 

Amphibos,  178 

Amynodon,    1 

Anchitherium,    79,    190,   203, 

210 

Ancodus,  170 
Ancylotherium,  126 
Animals,  Crescent-toothed,  137 

—  Odd-hoofed,  189 
-  Ohio,  233 

—  Pair-hoofed,  137 
Anoa,  179 

Anoplotherium,  80,  129 
Ant-bears,  124 
Antelope  arabica,  176 
Antelopes,  79,  173 

—  Saiga,  76 

Anthracotherium,  80,  142 
Anthropomorphic,  297 
Antilocapra,  161 
Appenzell,  cattle  of,  179 
Arctocyon,  80,  282,  285 
Arctocyonidae,  283 

Arno,  Val  d'  (Pliocene),  79 
Auchenia,  157 


CAT 

BABIBUSSA,  138 

Balaena,  250 

Baltavar  (Upper  Miocene),  79 

Bear,  280 

Bearded  Whale,  247 

Bear-dog,  280 

Bern  cattle,  179 

Bettongia,  100 

Bibos,  178 

Bibovina,  178 

Bison,  178,  179,  187 

Boar,  wild,  138 

Bos,  176,178 

Bradypus,  114 

Bramatherium,  172 

Brontotherium,  81,  199 

Bronze-dog,  264 

Bubalina,  178 

Buffalo,  186 

Buffelus,  178 

Bull-dog,  264 

Bunodonta,  137 

Bunotheria,  284 


CADICONA  Lignite  (Lower  Mio- 
cene), 79 
Cainotherium,  79,  182 


304 


INDEX 


CAM 

Camargue,  house  of,  221 
Camels,  154 
Camelus,  157 
Canidao,  259 
Canis,  259 

—  antarcticus,  262 

—  anthus,  262 

—  argentatus,  262 

—  azarje,  262,  268 

—  cancrivorus,  262 

—  fulvus,  262 

—  latrans,  262 

-  littoralis,  262 

-  lupaster,  264 

—  lupus,  264 

—  magellanicus,  262 

—  pallipes,  264 

—  suessi,  265 

—  vulpes,  260 

—  zerda,  262 

Cattle  of  Appenzell,   379 

-  173,  178 

—  Dutch,  179 

—  of  Bern,  179 

—  Short-headed,  189 

—  Tyrolese,  189 
Cats,  275 
Cave  Wolf,  265 

Central  German  Horse,  224 
Cervulus,  161 
Cervus  canadensis,  163 
Cetotherium,  251 
Chalicotherium,  201 
Chelys  fimbriata,  37 
Chlamydophorus,  120 
Chceropotamus,  142 
Chcerotherium,  142 
Cholospus,  149 
Colonoceras,  81 
Coryphodon,  80,  81,  132,  284 


DUC 

Creodonta,  282,  283,  284 
Crescentic-toothed       animals, 

137 

Ctenacodon,  100, 
Cynodictis,  271 
Cyon,  266 

DASYPUS,  120 

Dasyurus,  269 

Debruge,       Lignite        (Upper 

Eocene),  79 
Deer,  79 

—  Bed,  162 

—  Eein,  165 

—  Telemetacarpal,  163 
Diceratherium,  81 
Dichobune,  80 
Dicotyles,  138,  141 
Dicrocerus,  79,  161 
Didelphia,  93 
Didelphys,  97,  99 
Diluvial  Horse,  224 
Dingo,  262 
Dinoceras,  81,  241 
Dinocerata,  240 
Dinotherium,  79,  236 
Diphyodonta,  43 
Diplopus,  170 
Diprotodon,  103,  104 
Diptacodon,  81 
Dogs,  races  of,  259 

—  Bear- dog,  280 

—  Bronze-dog,  264 

—  Bull-dog,  264 

—  Viverrine  dog,  271 

—  wild  dogs  of  Africa,  264 
Dolphins,  248 
Dorcatherium,  79 
Dremotherium,  79 

Duck  Mole,  86 


INDEX 


305 


DTJT 

Dutch  cattle,179 
Dwarf  musk  deer,  167 


ECHIDNA,  86 

Egerkiiigen  (Middle    Eocene), 

80 

Eibiswald  (Middle  Miocene),  79 
Elasmotherium,  190,  197 
Elephants,  79,  228,  235 
Elk,  165 

Entelodon,  80,  282 
Eohippus,  81,  190,  213 
Eohyus,  143 
Eppelsheim  (Upper  Miocene), 

79 

Equus  caballus,  218 
• —  stenonis,  216 
Eutheria,  93 


FELTS,  276 

Fingered  animal,  293 
Fontainebleau,    sand    (of    the 

Lower  Miocene),  79 
Fox,  260 
Frontosus  race,  179 


GELOCUS,  79,  164,  170 

Georgsmiinde  (Middle  Eocene), 
79 

Gerard-le-Puy,  St.  (Lower  Mio- 
cene), 79 

Giraffe,  170 

Girdled  animals,  120 

Glossotherium,  124 

Glyptodon,  123,  124 

Greenland  seal,  290 

Giinzberg  (Middle  Eocene),  79 


JER 

HALICORE,  242 
Halitherium,  242 
Hampshire  (Upper  Eocene),  79 
Hatteria,  28 
Helaletes,  81,  193 
Helladotherium,  79,  172 
Helohyus,  143 
Hipparion,  79,  190,  203 
Hippopotamus,  144,  145,  146, 

203 
Hog-deer,  138 

-  wart,  138 

Hollow-horned  animals,  173 
Horse,  190,  201 

-  Diluvial,  224 

—  occidental,  223 

—  of  the  Camargue,  221 

—  of  Solutre,  220 

—  oriental  races  of,  223 

—  wolf-toothed,  210 
Hysernoschus,  167,  168 
Hyaena,  79,  280 
Hyanarctos,  280 
Hyamodon,  80,  282 
Hydaspitherium,  172 
Hydropotes,  163 
Hyopotamus,  168 
Hyrachyus,  81,  193 
Hyracodon,  81 
Hyracotherium,  80 
Hyrax,  241 


ICTICYON,  266 
Ictitherium,  79,  280 
Insectivora,  284,  286 


JACKAL,  264 
Jerboa,  76 


306 


INDEX 


LAI- 
LA    FERE,    Sandstcin    (Lower 

Eocene),  80 
Lama,  155 
Leberon      (Upper      Miocene), 

79 

Leptobos,  178 
Lignite   of  Cassino  (Pliocene), 

79 
London  clay   (Lower  Eocene), 

80 
Lophiodon,  190,  192 


MACHAIRODUS,  276 
Macrauchima,  228 
Macrotherium,  125 
Mammoth,  235 
Manatus,  242 
Mastodon,  79,  231 
Mauremont    (Middle   Eocene), 

80 

Megatherium,  81,  114 
Mesodonta,  284 
Mesohippus,  81 
Mesonychidee,  283 
Metatheria,  93 
Miacidffi,  283 
Microlestes,  98 
Miohippus,  81 
Monodelphia,  93 
Monophyndota,  43 
Montabuzard  (Middle  Eocene) 
79 

Montpellier,  marl  of,  79 
Moropus,  125 
Muntjak,  161 
Musk  deer,  167 
Mylodon,  114 


NECROLEMUR,  295 
Neoplagiaulax,  100 
Norwich  crag,  79 
Nototherium,  104 


OCCIDENTAL  HORSE,  223 
Odd-hoofed  animals,  189 
Oenigen  (Upper  Miocene),  79 
Ohio  animals,  233 
Oreodon,  81 
Oriental  races  of    the   horse, 

223 
Orleans,     sand      of      (Middle 

Miocene),  79 
Ornithorhyncha,  86 
Orohippus,  81,  190 
Otocyon,  268 
Oxyama,  81,  283,  285 
OxysBnidffi,  283 


PAIR-HOOFED  ANIMALS,  137 

Palffiochoarus,  142 

Palaeocyon,  282 

Palseonictis,  80 

Palaeoprionodon,  274 

Palaeotherium,  80,  190,  201 

Palorchestes,  104 

Parameryx,  156 

Paris  gypsum  (Upper  Eocene), 
79 

Paris  coarse  limestone  (Up- 
per Eocene),  80 

Pea  ore  (Middle  Eocene),  80 

Peccary,  130,  140 

Perchoerus,  143 

Phacochosrus,  138 

Phascolomys,  104 


INDEX 


307 


PHA 

Phascolotherium,  99 
Pigs,  70,  137,  141 
Pikermi  (Upper  Miocene),  79 
Plagiaulax,  99,  100 
Plesictis,  274 

Plesiometacarpal  deer,  1G3 
Pliauchenia,  157 
Pliohippus,  81,  190,  215 
Pliolophus,  80 
Poebrotherium,  159 
Poodle,  264 
Portacina,  178 
Primigenius  bos,  179 
Proaelurus,  275 
Probubalus,  178,  179 
Procamelus,  156 
Procervulus,  160 
Prorastomus,  244 
Protohippus,  81,  190,  214 
Protolabos,  156 
Prototheria,  93 
Prox,  160 
Pseudaelurus,  275 
Pterodon,  80,  282 


QUERCY     PHOSPHORITE    (Upper 
Eocene),  79 


BED  DEER,  162 

Rein  deer,  165 

Rhinoceros,  79,  81,  190,  194 

—  minutus,  198 

Rhinolophus,  294 

Rhytina,  243 

River  horse,  144 

Ronzon,  lime  rocks  of  (Lower 

Miocene),  79 
Ruminants,  150 


TYR 

SABRE-TOOTHED  TIGER,  277 

Saiga  antelope,  76 

Sand  of  Orleans  (Middle  Eo- 
cene), 79 

Sansan  (Middle  Miocene),  79 

Selenodonta,  137 

Short-headed  cattle,  189 

Shorthorn  bull,  175 

Simocyon,  79 

Sivalik  hills  (Upper  Miocene), 
79 

Sivatherium,  172 

Sloth,  giant,  113 

Smooth  whale,  250 

Soissonnais,  lignite  of  (Lower 
Eocene),  80 

Solutre,  horses  of,  220 

Squalodon,  251 

Stegodon,  234 

Stenoplesictis,  274 

Strata,  tertiary,  of  N.  America, 
81 


T^NIODONTA,  284 

Tapir,  79,  189, 190 
Tapiravus,  81,  193 
Taurina,  178 
Telemetacarpal  deev,  163 
Tertiary  strata  of  N.  America, 

81 

Thylacinus,  269 
Thylacoleo,  102 
Tillodonta,  284 
Tillotherium,  81,  286 
Tinohyus,  143 
Toothed  whales,  247 
Tragulidse,  167 
Trichechus,  287 
Tyrolese  cattle,  189 


308 


INDEX 


TIRO 


UllOMASTlX,  28 

Ursus,  280 


VAL  D'ARNO  (Pliocene),  79 
Vespertilio,  294 
Vienna  basin,  79 
ViverriB,  274 
Viverrine  dog,  271 


WALBUS,  287 
Wapiti,  163 
Wart-hog,  138 
Whales,  toothed,  247 
—  bearded,  247 


ZEU 

Wild  boar,  138 
Wild  dog  of  Africa,  264 
Wolf,  265 
—  Indian,  264 
Wolf-tooth  of  horse,  210 
Wombat,  104,  293 


XlPHODON, 182 

Xiphodonthedum,  182 


YAK, 179 


ZEOGLODON,  251 


THIS  BOOK  IS  DUE  ON  THE  LAST  DATE 
STAMPED  BELOW 


AN  INITIAL  PINE  OF  25  CENTS 

WILL  BE  ASSESSED  FOR  FAILURE  TO  RETURN 
THIS  BOOK  ON  THE  DATE  DUE.  THE  PENALTY 
WILL  INCREASE  TO  5O  CENTS  ON  THE  FOURTH 
DAY  AND  TO  $1.OO  ON  THE  SEVENTH  DAY 
OVERDUE. 


BIOLOGY  LIBRARY 


tot 


HEC  9     1996 


OCT.?     1942 


APR  19  1951 


APR  1 7  1951 


LD  21-5m-7,'33 


k    **   .^ii^iSSy/tWPNi^  V 


CIENTIFIC 


